Catherine E De Vries
email: cvries@fsw.leidenuniv.nl

conditional logit regression European integration EU issue voting

come

Sleeping Giant: Fact or

Fairytale?

How European Integration Affects National Elections

Catherine E. de Vries

Leiden University, The Netherlands

A B S T R A C T

Do attitudes towards European integration influence vote choice in national elections -a phenomenon I refer to as European Union (EU) issue voting? Evidence concerning EU issue voting is thus far mixed. Some scholars conclude that an electoral connection exists between European and national politics, whereas others claim that European integration has had very few observable effects on national elections. A resolution emerges when the conditional nature of EU issue voting is acknowledged. Specifically, EU issue voting is more likely to occur in elections in which both the extent of partisan conflict over European integration and the degree of EU issue salience among voters are high. Using a conditional logit model, I illustrate the conditional nature of EU issue voting by comparing UK, Danish, Dutch and German elections between 1992 and 2002.

Introduction

In the aftermath of the 2005 Dutch and French referendums on the Draft Constitutional Treaty, the discussion regarding an alleged gap between political elites and the masses has intensified [START_REF] Hooghe | Europe's Blues: Theoretical Soul-Searching after the Rejection of the European Constitution[END_REF][START_REF] Gabel | Mixed Messages: Party Dissent and Mass Opinion on European Integration[END_REF][START_REF] Steenbergen | Who's Cueing Whom? Mass-Elite Linkages and the Future of European Integration[END_REF]. With the expansion of European Union (EU) jurisdictional authority over a range of policy areas from market integration and employment policy to foreign policy and immigration, the introduction of a single currency, EU enlargement and the negotiation of a 'Constitution' for Europe, European integration has motored full speed ahead. But not all citizens appear to like the speed with which or the direction in which the European endeavour is moving. There appears real potential for political mobilization against the European project. Hence the notion coined by Van der Eijk and Franklin that there is a 'sleeping giant' of public opinion scepticism that could be woken up by political entrepreneurs. This in turn could alter elections or even change the structure of domestic political competition (Van der [START_REF] Van Der Eijk | Potential for Contestation on European Matters at National Elections in Europe[END_REF].

Research consistent with the sleeping giant thesis demonstrates that attitudes towards European integration are indeed capable of influencing national vote choice [START_REF] Evans | Euroscepticism and Conservative Electoral Support: How an Asset Became a Liability[END_REF][START_REF] Evans | European Integration, Party Politics and Voting in the 2001 Election[END_REF][START_REF] Gabel | European Integration, Voters and National Politics[END_REF][START_REF] Tillman | The European Union at the Ballot Box? European Integration and Voting Behavior in the New Member States[END_REF]. There is also evidence that public opinion helps shape elite preferences concerning the EU and vice versa [START_REF] Carrubba | The Electoral Connection in European Union Politics[END_REF][START_REF] Steenbergen | Who's Cueing Whom? Mass-Elite Linkages and the Future of European Integration[END_REF]. This work suggests that there is some sort of 'electoral connection' between European and national politics [START_REF] Carrubba | The Electoral Connection in European Union Politics[END_REF]. However, other scholars note that Europeanization effects on domestic political competition are weak [START_REF] Mair | The Limited Impact of Europe on National Party Systems[END_REF]Sitter, 2001;[START_REF] Krouwel | All Politics Is National, but Policy Is Supra-National: A Decisive Discrepancy[END_REF][START_REF] Van Holsteyn | Reus in de Polder? Nederlandse Kiezers en het Electorale Belang van Europese Integratie[END_REF]. Mair (2000: 31) argues that European integration has had virtually no effect on the format of national party systems, which is echoed in the conclusion by [START_REF] Krouwel | All Politics Is National, but Policy Is Supra-National: A Decisive Discrepancy[END_REF] that, although policy-making is increasingly supranational in character, politics is still primarily a national affair.

What are we to make of these competing theses? In other words, do attitudes towards European integration influence vote choice in national elections, or not? In this article, I develop an argument that emphasizes the conditional nature of EU issue voting. EU issue voting is defined as the process in which attitudes towards European integration translate into national vote choice. I argue and empirically substantiate that the level of EU issue voting is conditional on the degree of EU issue salience among voters and the extent of partisan conflict over Europe. Do citizens care about Europe, and do parties provide them with meaningful choice? The available evidence also suggests that conflict and salience are mediated by the extent to which Eurosceptic political entrepreneurs at the ideological extremes can mobilize the EU issue. This article proceeds as follows. After a brief discussion of the sleeping giant thesis, the conceptual starting point of my argument, I theorize the conditional nature of EU issue voting. I then highlight the role of Eurosceptic political entrepreneurs on the far right and far left in mobilizing the EU issue in national electoral politics. Finally, I examine EU issue voting in Denmark, Germany, the Netherlands and the United Kingdom (UK), which provide sharply contrasting contexts for EU issue voting.

The conditional nature of EU issue voting

An interesting conceptual starting point for EU issue voting lies in the thesis developed by [START_REF] Van Der Eijk | Potential for Contestation on European Matters at National Elections in Europe[END_REF]. They argue that the EU issue presents a 'sleeping giant' to the extent that it divides voters without giving them an immediate outlet in party competition.

Two elements underlie the thesis. For an issue to be a giant, EU orientations of voters should resemble 'real' attitudes rather than random responses; i.e. most people should have an opinion and these opinions should exhibit some meaningful variation. If EU attitudes are 'non-attitudes', one would expect to find a high number of missing values, low agreement and low extremity (Van der [START_REF] Van Der Eijk | Potential for Contestation on European Matters at National Elections in Europe[END_REF]; see also [START_REF] Converse | The Nature of Belief Systems in Mass Public[END_REF][START_REF] Van Der Eijk | Measuring Agreement in Ordered Scales: Quality and Quantity[END_REF]. The authors show that a surprisingly large proportion of voters hold 'real' attitudes and display meaningful variation in EU preferences (Van der Eijk and Franklin, 2004: 37-8). The giant is sleeping because voters find it impossible to express their views on Europe at the ballot box. In most member states, inter-party competition on European integration is much more limited than on left/right issues, whereas voters appear as divided on Europe as on left/right issues (Van der Eijk and Franklin, 2004: 39-41). Thus, 'the pro-/anti-EU orientation . . . constitutes something of a "sleeping giant" that has the potential, if awakened, to impel voters to political behaviour that (because of its degree of orthogonality with left/right orientations) undercuts the bases for contemporary party mobilisation in many, if not most, European polities ' (2004: 33).

The sleeping giant thesis assumes that EU contention is most likely to originate from public opinion -though mediated via political entrepreneurs. The reason for this, according to [START_REF] Van Der Eijk | Potential for Contestation on European Matters at National Elections in Europe[END_REF], is that, although most voters are 'ready' to use EU preferences, political parties for the most part are inclined to downplay the EU issue by subsuming it into the left/right issue. However, 'voter readiness is not enough -some policy entrepreneur or entrepreneurs have to come along who are willing to capitalise these preconditions in order to win votes that otherwise would have gone elsewhere' (Van der Eijk and Franklin, 2004: 48). Voters show meaningful variation on the EU issue and this 'giant' of public Euroscepticism waits to be exploited by political entrepreneurs.

What happens if we relax this assumption? Could not EU issue voting emerge out of situations where inter-party conflict on European integration precedes and provokes voter salience? This latter perspective is highlighted in US literature on issue evolution (Carmines andStimson, 1986, 1989;[START_REF] Abramowitz | Issue Evolution Reconsidered[END_REF][START_REF] Adams | Abortion: Evidence of an Issue Evolution[END_REF][START_REF] Layman | Party Polarization and "Conflict Extension" in the American Electorate[END_REF][START_REF] Stimson | Tides of Consent: How Opinion Movements Shape American Politics[END_REF]. The notion of issue evolution developed by Carmines andStimson (1986, 1989) is based on the view that party elites set in motion the process by which an issue becomes salient. The term refers to the emergence and development of issues that invoke public interest, which under the condition of durable divisiveness may eventually alter the link between voters and parties and lead to mass realignment (Carmines and Stimson, 1989: 11). Carmines and Stimson sketch a sequence explicating how elite change may result in electoral change.

The first step is the (re-)phrasing of a potentially contentious issue in partisan terms. This may be triggered by strategic calculation -a situation in which opposition parties identify a previously non-salient issue in the anticipation that it may help them upset an existing majority. The underlying assumption here is that of vote maximization [START_REF] Downs | An Economic Theory of Democracy[END_REF]. But contention may also be provoked by a 'critical moment' -an exogenous event -which draws attention to an issue and which prompts partisan competition (Carmines and Stimson, 1986: 902). Either way, the issue becomes contentious. The second and third steps extend this to voters. Carmines and Stimson emphasize how party priming, framing and cueing make voters aware of the differences in party positioning on the new issue, as well as make voters care about the issue. This is what they refer to as achieving clarity and affect (1986: 902-3). The assumption is, then, that the public will follow elites. According to Carmines andStimson (1986, 1989), issues are expected to gain political relevance when both of the following conditions are met. First, there should be conflict among parties, and this conflict should be perceived by voters (perceived partisan conflict, or contention + clarity). Second, voters should care about the issue (issue salience, or affect).

Carmines and Stimson's 'issue evolution' perspective and Van der Eijk and Franklin's 'sleeping giant' scenario present two different pathways to EU issue voting. The latter model presumes that EU issue voting begins with public opinion mobilization; that is to say, when voters care about the issue, parties will respond. EU issue voting constitutes a bottom-up phenomenon. The former model highlights the role of political parties in driving EU issue voting in a top-down fashion. In this case, the process starts with party repositioning and, as parties play up their differences, voters respond. Despite their differences, the two perspectives share a basic insight: both identify perceived partisan conflict and issue salience as crucial ingredients for issue voting. I build on this to theorize that EU issue voting is likely only to the extent that there is a combination of high perceived partisan conflict and high issue salience regarding European integration (EU Issue Voting Hypothesis). 1 One or the other is not sufficient to trigger EU issue voting.

The role of extremist political entrepreneurs in the EU issue voting process

After highlighting the conditions under which EU issue voting is likely to take place, it is important to reflect on when partisan conflict and voter salience regarding European integration are expected to be high. Relying on the literature on party strategy in general and on studies regarding party positioning on European integration specifically, I suggest that Eurosceptic parties at the political extremes are crucial in this respect.

Parties on the far right or far left have an interest in restructuring contestation to broaden their voter base, because their extreme position on the left/right dimension is likely to provide a low ceiling to their support base. As a result, these parties have an incentive 'to find some alternative [issue] that beats the current winner' (Riker, 1982: 209). This may bring about an electoral reorientation and thus new voters. The kinds of issues rational parties on the extreme right and left can be expected to pick up are issues maximizing consistency with their ideological platform, while at the same time minimizing positional distance with some untapped public concern [START_REF] Hinich | Political Ideology, Communication, and Community[END_REF]. The EU issue could be such an issue, precisely because (a) Euroscepticism is ideologically consistent with these parties' more general criticism of the political-economic status quo, and (b) public opinion is, on average, much more Eurosceptic than mainstream elites. [START_REF] Hooghe | Europe Divided? Elites vs. Public Opinion on European Integration[END_REF] refers to this phenomenon as 'Europe divided'. So, there is an unexploited voter potential. All the while, opposition to European integration should enhance extremist parties' credibility, because it fits rather nicely in their ideological profile (see [START_REF] Hinich | Political Ideology, Communication, and Community[END_REF].

The existence of an extremist, Eurosceptic political entrepreneur is not enough, however, to raise perceived partisan conflict and voter salience regarding European integration. Parties on the extremes of the political spectrum have to actively play up the EU issue, i.e. they need to decide to give the EU issue central importance in their electoral campaigns. Both saliency theory of party competition [START_REF] Budge | Explaining and Predicting Elections: Issue Effects and Party Strategies in Twenty-Three Democracies[END_REF] and the theory of issue ownership [START_REF] Petrocik | Issue Ownership in Presidential Elections, with a 1980 Case Study[END_REF] inform us that political parties are compelled to pick certain core issues in their electoral campaign. By strategically emphasizing some issues and de-emphasizing others, voters come to associate certain parties with specific issues. However, neither theory gives us much guidance on which issues parties are likely to choose. The literature on party positioning regarding European integration can provide some clues. We know, for example, that mainstream parties have no incentive to play up the EU issue because they are generally supportive of the integration process; they have often been part of governing coalitions throughout Western Europe and were therefore largely responsible for the course of integration. Extreme, Eurosceptic parties, on the other hand, have an electoral incentive to play up the EU issue [START_REF] Taggart | A Touchtone of Dissent: Euroskepticism in Contemporary Western European Party Systems[END_REF][START_REF] Netjes | The Salience of the European Integration Issue: Three Data Sources Compared[END_REF]. Moreover, Eurosceptism is rooted in the partisan ideology of far left and far right parties, albeit for different reasons. Radical right parties oppose European integration because it erodes national sovereignty and national identity; the radical left resists further integration in Europe owing to its neo-liberal character [START_REF] Hooghe | Does Left/Right Structure Party Positions on European Integration[END_REF][START_REF] Kopecky | The Two Sides of Euroscepticism[END_REF].

So, far left and far right political entrepreneurs have a strategic incentive to mobilize the EU issue in order to reap electoral gains [START_REF] Taggart | A Touchtone of Dissent: Euroskepticism in Contemporary Western European Party Systems[END_REF][START_REF] Van Der Eijk | Potential for Contestation on European Matters at National Elections in Europe[END_REF]. When they do so, perceived partisan conflict and voter salience regarding European integration should rise as a result. Consequently, the more the extremist parties actively play up the anti-EU card, the higher perceived partisan conflict and issue salience can be expected to be (Extremist Parties Hypothesis).

To sum up, two hypotheses guide the empirical analysis. First, I expect the extent of EU issue voting to be conditional on the degree of EU issue salience among voters and the extent of partisan conflict on Europe (EU Issue Voting Hypothesis). Secondly, partisan conflict and issue salience are mediated by the extent to which Eurosceptic political entrepreneurs at the ideological extremes mobilize the EU issue (Extremist Parties Hypothesis). Before we turn to the empirical examination of these hypotheses, let me first introduce the data, operationalizations and methods used.

Data, operationalizations and methods

To examine the relationship between attitudes on European integration and vote choice in national elections, I employ individual-level survey data from the British general election surveys of 1992, 1997 and 2001, the Danish national election surveys of 1994, 1998 and 2001, the Dutch national election surveys of 1994, 1998 and 2002 and the German election surveys of 1998 and 2002. 2 The data show considerable variation in EU issue salience and perceived partisan conflict on Europe and thus provide an excellent test of the EU Issue Voting Hypothesis. Moreover, the question wordings for the dependent and independent variables used in the empirical analysis are very similar across the different surveys.

The analysis proceeds in three parts. First, I determine the extent of perceived partisan conflict and issue salience in each election. Next, I assess the validity of the EU Issue Voting Hypothesis by examining whether EU issue voting is indeed more extensive when partisan conflict and issue salience are high. Finally, I evaluate the Extremist Party Hypothesis by presenting evidence of the role of extremist political entrepreneurs in the EU issue voting process.

What is the extent of perceived partisan conflict and issue salience regarding Europe? Perceived partisan conflict is the ratio of party dispersion on EU issues to dispersion in terms of left/right ideology, which I measure as the standard deviation of voters' EU and left/right party placements in the respective national election survey data. For the UK 1992 elections, I lack voters' perceptions of parties' EU positions, and so I rely on the Chapel Hill expert survey data on party positioning on European integration to determine party positions on Europe. 3 If the ratio takes on the value of 1 or higher, then partisan conflict on EU issues is considered high. To measure EU issue salience, I use the question from the relevant national election surveys asking respondents to name the most important problems facing their countries. Some scholars have questioned whether this item truly taps issue salience on the grounds that it may conflate the importance of an issue -salience -with the problematic nature of the same issue [START_REF] Wlezien | On the Salience of Political Issues: The Problem with "Most Important Problem[END_REF]. Although this may be a valid concern for elites or sophisticated respondents, it is not clear whether ordinary citizens are in a position to distinguish the most important issues -that is, high up on the priority list -from the most problematic -that is, difficult to solve by public policy.

The second part of the empirical analysis examines the extent of EU issue voting. In order to do this, I employ a conditional logit regression model. Since my dependent variable is a categorical variable with multiple values, i.e. vote choice for different parties, I need to address several methodological concerns (see [START_REF] Alvarez | When Politics and Models Collide: Estimating Models of Multiparty Elections[END_REF][START_REF] Agresti | Categorical Data Analysis[END_REF]. First, since the probability of voting for a party can vary only between 0 and 1, ordinary least squares regression analysis is ruled out. Moreover, because I am interested in how the characteristics of parties (i.e. their positions on European integration relative to voter positions) influence vote choice within a spatial framework, I use a conditional logit rather than a multinomial logit model (see [START_REF] Alvarez | When Politics and Models Collide: Estimating Models of Multiparty Elections[END_REF]. The multinomial logit model focuses on information about individual voters rather than issue positions of parties and/or candidates and is therefore less suitable for modelling electoral behaviour in a spatial setting. The conditional logit model, on the other hand, allows for the examination of both party and respondent positions on a given issue. 4 The model consists of four predictors: the distance between a respondent's self-placement and a party's position on European integration (EU issue distance), left/right, immigration policy and environmental policy scales. I also include several socioeconomic control variables, such as gender, religiosity, income and education.

The dependent variable is the vote choice of respondents in a given parliamentary election. To construct the EU distance variable -the crown independent variable -I subtract a respondent's self-placement from a respondent's party-placement on an EU scale for each individual party. I then square this distance to derive an Euclidean distance measure. Respondents were asked to place themselves, as well as several political parties, on a five-point European integration scale, where 1 stands for exit from the EU and 5 stands for the fastest possible build-up of the EU. Voters are expected to choose the party that most accurately resembles their EU positions, i.e. the smallest distance hypothesis. 5 So, if EU issue voting occurs, the effect of EU issue distance should be negative and significant. In other words, an increase in disagreement between a respondent's EU position and a party's EU position should lead to a decrease in the likelihood of the respondent voting for the party.

To assess the importance of the EU issue in relation to other concerns, I also include three non-EU-related policy variables (left/right and two new politics policies, namely immigration and environmental policy). Each is constructed in the same manner as EU issue distance. 6 Table 1 summarizes the operationalizations of the variables employed in the conditional logit regression analysis.

In the third and final step of the empirical analysis, I evaluate the role of extremist political entrepreneurs in the EU issue voting process. The parties included are both Eurosceptic and extremist in terms of left/right positioning. Left or right extremist parties are those parties that are one standard deviation below or above the mean left/right ideological position of all parties in a country. Eurosceptic parties are those parties that are one standard deviation below the mean position on European integration for all parties in a country. The parties' left/right and EU positions are based on the respondents' party-placements included in the respective national election surveys, with the exception of EU positions in the 1992 UK election, for which I used the Chapel Hill expert survey data on party positioning.

I argued above that the mere presence of an extremist, Eurosceptic political entrepreneur is not enough; these parties have to actively play up the EU issue in their electoral campaigns. To get a sense of the importance of the EU issue for extremist, Eurosceptic parties I use the Chapel Hill expert survey

Dependent variable

Vote choice

Vote choice for a particular party in a given election.

Independent variables EU distance

Operationalized by subtracting a respondent's self-placement from a respondent's party-placement on a five-point European integration scale (where 1 stands for exit out of the EU and 5 stands for the fastest possible build-up of the EU) for each party. I then squared this distance to derive an Euclidian distance measure.

(0 = high correspondence between self-and party-placement; 16 = low correspondence between self-and party-placement).

Left/right distance Operationalized by subtracting a respondent's self-placement from a respondent's party-placement on a five-point left/right ideological scale (where 1 indicates left and 5 indicates right) for each party. I then squared this distance to derive an Euclidian distance measure.

(0 = high correspondence between self-and party-placement; 16 = low correspondence between self-and party-placement).

Immigration distance Operationalized by subtracting a respondent's self-placement from a respondent's party-placement on a five-point immigration scale (where 1 indicates restrict immigration and 5 indicates welcome more immigrants) for each party. I then squared this distance to derive an Euclidian distance measure.

(0 = high correspondence between self-and party-placement; 16 = low correspondence between self-and party-placement).

Not included in the British election surveys.

Environment distance Operationalized by subtracting a respondent's self-placement from a respondent's party-placement on a five-point environment scale (where 1 indicates not very green policy and 5 indicates green policy) for each party. I then squared this distance to derive an Euclidian distance measure.

(0 = high correspondence between self-and party-placement; 16 = low correspondence between self-and party-placement).

Not included in the British election surveys. data on party positioning on European integration. In these surveys, experts were asked to evaluate the relative importance of the EU issue to the party's public stance on a five-point scale, where 1 indicates that European integration is of no importance to the party and 5 signifies that European integration is the most important issue for the party (in 2002 EU issue salience was measured on a 4-point scale, in order to guarantee comparability across surveys, the 2003 item was recoded to a 5-point scale).

Empirical analysis

Let me begin by determining the extent of perceived partisan conflict and issue salience regarding European integration in the UK, Danish, Dutch and German elections. Table 2 compares the perceived degree of conflict among parties over the EU issue relative to that in terms of left/right ideology for the 11 elections. I measure perceived partisan conflict by the ratio of the standard deviation of party positions on European integration and the standard deviation of party positions on the left/right dimension as perceived by voters. A value above 1 means that, in the eyes of the voters, parties diverge more on European integration than on left/right issues. The differences between the cases are considerable. For the UK and Danish elections, the ratio of European integration versus left/right equals or even exceeds 1. This suggests that UK and Danish parties represent a broad range of opinions on Europe -as broad, and sometimes broader, than on the classic left/right dimension. That is not at all true for German and Dutch elections, with the partial exception of the Dutch 2002 elections.

These data are consistent with what we know about UK, Danish, Dutch and German politics. European integration has caused major disagreement in the Danish and UK party system and tensions in several major political parties, especially within the Danish Social Democrats and the UK Conservatives [START_REF] Worre | Denmark: Second-Order Containment[END_REF][START_REF] Berrington | Europe, Thatcherism and Traditionalism: Opinion, Rebellion and the Maastricht Treaty in the Backbench Conservative Party, 1992-94[END_REF]. In Denmark, closely contested referendums on EU issues, of which there have been six so far, have deepened party divisions on Europe [START_REF] Buch | The Danes and Europe: From EC 1972 to Euro 2000 -Elections, Referendums and Attitudes[END_REF]. The 'no' camp has mainly framed its opposition in terms of the danger of a small country being swallowed by a big EU; the EU is developing into a 'super state and Denmark would soon become a municipality of Europe' (Friis, 1998: 2). For example, the Danish People's Party (Danske Folkeparti -DF) voiced its opposition to the Amsterdam Treaty in the 1998 campaign by using the slogan 'vote Danish, vote no'. Although two-thirds of UK voters supported membership in the European Economic Community in 1975, public and party-based Euroscepticism has been on the rise ever since [START_REF] Spiering | British Euroscepticism[END_REF]. Opposition towards Europe in UK party politics is especially associated with right-wing factions within the Conservative Party, which are concerned about UK sovereignty in the context of further European integration [START_REF] Marks | The Past and the Present: A Cleavage Theory of Party Response to European Integration[END_REF][START_REF] Gifford | The Rise of Post-Imperial Populism: The Case of Right-Wing Euroscepticism in Britain[END_REF].

The EU issue generated much less partisan conflict in Dutch and German politics. Dutch and German citizens and political parties have long been regarded as Euro-enthusiasts. Opposition to further European integration was seen as 'not done'. Recently, however, this traditional attitude of consent has given way to moderate Euroscepticism [START_REF] Busch | German Euroscepticism[END_REF][START_REF] Thomassen | Nederlanders en Europa. Een Bekoelde Liefde?[END_REF]. Although German political parties have so far not exploited this change in mood, Dutch political parties, especially those on the extreme right, seem increasingly willing to play up anti-EU sentiment [START_REF] Lees | Dark Matter: Institutional Constraints and the Failure of Party-Based Euro-scepticism in Germany[END_REF][START_REF] Pellikaan | Een Ruimtelijk Model voor Onderzoek naar Euroscepsis toegepast op Nederlandse en Vlaamse Partijen[END_REF]. In the mid-1990s, the parliamentary leader of the Liberal Party (Volkspartij voor Vrijheid en Democratie -VVD), Frits Bolkestein, challenged the Dutch consensus by expressing reservations regarding the integration process. Bolkestein opposed further political integration and felt, like many other Conservative leaders in Europe, that integration should remain primarily economic [START_REF] Harmsen | Eurosepticism in the Netherlands: Stirrings of Dissent[END_REF]. Although this view was not shared by all VVD parliamentarians, Bolkestein's dissent opened the door for other parties to become more openly Eurosceptic. As Table 2 shows, perceived inter-party conflict regarding the EU almost doubled between the 1998 and 2002 elections. This change is primarily due to the Eurosceptic position of the List Pim Fortuyn (Lijst Pim Fortuyn -LPF) [START_REF] Pellikaan | Een Ruimtelijk Model voor Onderzoek naar Euroscepsis toegepast op Nederlandse en Vlaamse Partijen[END_REF].

What about EU issue salience in public opinion? Figure 1 compares salience in UK, Danish, Dutch and German elections. EU issue salience is measured with a question asking respondents to name the most important issues facing their country. This is a tough question, because it requires voters to weigh the relative importance of the EU against other pressing issues. One would not expect many voters to see the EU as one of the most important issues in national elections. Still, in the United Kingdom no less than 8.8% in 1997 and as much as 10.9% in 2001 viewed issues regarding European integration as important to their country. This percentage was lower in the 1992 campaign. In Denmark, too, about 4.5% of voters saw European integration and the euro as important issues for their country in 1994 and 1998. In contrast to Denmark and the United Kingdom, issue salience in Germany and the Netherlands has been consistently low. Recent studies show that European integration was virtually absent from Dutch and German electoral campaigns (see [START_REF] Poguntke | Germany[END_REF][START_REF] Poguntke | Germany[END_REF]Thomassen et al., 2000;[START_REF] Van Holsteyn | Reus in de Polder? Nederlandse Kiezers en het Electorale Belang van Europese Integratie[END_REF].

In line with the EU Issue Voting Hypothesis, I would expect EU issue voting to be most extensive in the three UK and Danish elections, owing to the relatively high level of perceived partisan conflict and EU issue salience among voters. In the German and Dutch elections, however, both partisan conflict and public opinion salience remain low. Hence, in these elections, I expect voters to base their vote choice on considerations other than EU preferences. The Dutch 2002 election is interesting because, with the electoral debut of the Pim Fortuyn movement, partisan conflict regarding European integration almost doubled compared with 1998. However, left/right conflict still clearly surpassed conflict over European integration and EU issue salience among the Dutch electorate remained very low, and so I predict no EU issue voting in this election. Do the expectations about the degree of EU issue voting correspond to reality? Table 3 presents the key results of the conditional logit regression analyses. The reader is referred to a web appendix for detailed results. 7 EU issue voting exists in all three elections in Denmark and the United Kingdom, but not in the Dutch and German elections. In the Dutch and German elections, the coefficient of the EU issue distance variable is not significant. In UK and Danish elections, in contrast, the overall effect of the proximity between voters and parties in terms of the EU issue on national vote choice is negative and significant. In other words, an increase in divergence between a respondent's and a party's EU position leads to a decrease in the likelihood of the respondent voting for the party. More specific interpretations of these results are possible by examining the odds ratios reported in Table 3 [START_REF] Agresti | Categorical Data Analysis[END_REF][START_REF] Long | Regression Models for Categorical Dependent Variables Using Stata[END_REF]. The odds ratio refers to the change in the odds of the outcome for a unit increase in the predictor. Note that an odds ratio greater than 1 indicates a positive relationship, an odds ratio smaller than 1 indicates a negative relationship; and an odds ratio of 1 indicates no relationship. Odds ratios can be expressed as percent changes by using the following formula: 100*(odds ratio -1). 8 In the case of the 1994 Danish election, the percentage by which the odds of voting for a party change for a unit increase in EU issue distance amounts to -14%, i.e. 100*(0.86 -1), while for a unit increase in left/right issue distance the odds decrease by -69%. For the 2001 Danish election, the change in the odds of voting for a party as a result of a unit increase in EU issue distance is, at -5%, lower than in 1994. This is not surprising in light of the fact that Figure 1 has already indicated that the salience of the EU issue was lower in the 2001 election campaign compared with the 1994 election.

The change in the odds of voting for a party as a result of a unit increase in EU issue distance is of similar magnitude across the three UK elections. The percentage change in the odds is -16% in 1992, -15% in 1997 and -13% in 2001. The UK results also show that, similar to the Danish results, the effect of the left/right distance on vote choice is clearly higher than the effect of the EU issue distance. The percentage change in odds of voting for a party as a ---------------------------------------------------------------------------- ---------------------------------------------------------- ---------------------------------------------------------------------------- ------------------------------------------------------------------------ Notes: Table entries are conditional logit regression coefficients with standard errors in parentheses and odds ratios. The dependent variable is a respondent's vote choice for a particular party in a given election.

N.a. indicates that not all the variables necessary to construct the distance measures were available in the respective surveys. * significant at p < .05 level.

result of a unit increase in left/right issue distance is -34% in 1992 and even larger in the 2001 UK election, namely -43%. This is not surprising because previous research tells us that the left/right dimension is the main predictor of vote choice (Van der [START_REF] Van Der Eijk | Electoral Change in the Netherlands[END_REF][START_REF] Van Der Eijk | Policy Preferences and Party Choice[END_REF].

The results indicate that the EU issue contributes significantly to an explanation of voting behaviour in Danish and UK elections. This finding is consistent with my conjectures and is robust even when controlling for other factors influencing vote choice, such as attitudes on left/right issues, immigration and the environment as well as education, income and religion. 9 Thus, the EU issue contributes significantly to voting behaviour and does so independently from the left/right dimension and new politics. Moreover, the results signify that EU issue voting is absent from elections in which EU issue salience and perceived conflict regarding Europe are low. In Dutch and German elections, EU issue distance does not significantly contribute to our understanding of voting behaviour. Hence, the findings laid out in Table 3 support the EU Issue Voting Hypothesis.

An additional way of testing the validity of the EU Issue Voting Hypothesis is to compare associations between the extent of EU issue voting and the extent to which an election fits the EU issue voting conditions, that is to say, where perceived partisan conflict and issue salience reinforce each other. I measure the extent of EU issue voting in terms of the relative improvement in R 2 , i.e. the increase in explained variance when the EU issue distance variable is added to the base conditional logit regression model. There is a strong association between the extent of EU issue voting and the extent of partisan conflict and issue salience (operationalized as an interaction of the two), namely r = .88, which is significant at the p ≤ .001 level (two-tailed). Now we know when (i.e. under which conditions) EU issue voting is likely to occur, but are still left with the question of why perceived partisan conflict and issue salience regarding European integration varies across elections. Above I highlighted the crucial role of Eurosceptic political entrepreneurs on the left and right extremes. Figure 2 summarizes the EU issue salience for Eurosceptic left and right extremist parties in Denmark, Germany, the Netherlands and the United Kingdom from 1992 to 2002. EU issue salience ranges from 1 ('low salience') to 3 ('an important issue') to 5 ('most important issue').

The parties included are both Eurosceptic and extremist in terms of left/right positioning. Recall that, for left/right extremism, I use the following criterion: parties that are one standard deviation below or above the mean left/right ideological position of all parties in a country as well as one standard deviation below the mean position on European integration for all parties in a country. Figure 2 includes the usual suspects such as the Danish People's Party (DF) or the List Pim Fortuyn (LPF). The UK Conservative Party is also classified as an extremist, Eurosceptic party, which is consistent with the criteria I use to identify such parties. It is openly Eurosceptic and it is also more than one standard deviation to the right of the median party position on the left/right dimension.

Whereas UK and Danish extremist, Eurosceptic parties clearly view the EU issue as important, Dutch and German extremist political entrepreneurs do not. The level of EU issue salience of the extremist, Eurosceptic parties in the Netherlands and Germany between 1992 and 2002 is well below 3, indicating that the issue is not important for the public stance of these parties. The salience of the EU issue to extremist, Eurosceptic political parties is quite highly correlated with perceived partisan conflict on Europe and EU issue salience in the election as a whole, with r = .64 and r = .58 respectively (significant at the p ≤ .005 level two-tailed). Figure 2 highlights the fact that, in elections in which EU issue voting exists (that is, in the UK and Danish elections), extremist, Eurosceptic political entrepreneurs actively play up the EU issue, whereas in those elections in which EU issue voting is absent (i.e. the Dutch and German elections) extremist parties refrain from doing so. Incidentally, the UK and Denmark are also the countries where parties A more rigorous examination of the role of extremist, Eurosceptic political entrepreneurs is beyond the scope of this analysis, but the initial findings presented above are in line with the Extremist Parties Hypothesis and show that extremist, Eurosceptic parties may indeed play a crucial role in increasing public salience or mobilizing partisan conflict regarding European integration.

Concluding remarks

When might European integration influence national elections? This article has explored the potential for EU contestation in UK, Danish, Dutch and German general elections in the 1990s and early 2000s. The article argues and empirically substantiates that the extent of EU issue voting is conditional upon the salience of the issue for voters and the extent of partisan conflict. Both conditions, I argue, are open to manipulation by political parties, especially political entrepreneurs on the far right or far left of the political spectrum. In some countries (such as the Netherlands and Germany), voters do not care about the European integration issue and political parties do not compete on the issue; thus, we find no evidence of EU issue voting. In other countries (such as Denmark and the United Kingdom), issue salience and partisan conflict regarding European integration are high and EU preferences have influenced national vote choice.

The double-barrelled conditional nature of EU issue voting is clearly highlighted in the 2002 Dutch election. Even though partisan conflict over European integration nearly doubled in 2002 compared with 1998, this increase did not result in EU issue voting because the European issue does not (yet?) stir Dutch voters. As long as the public does not care about Europe, Europe is not going to bite in national elections. But this situation is not cast in stone: a political entrepreneur seeking to shift domestic debate away from left/right issues and utilizing growing discontent regarding Europe may change that.

Of course, this study has limitations. First of all, although it shows that EU issue voting varies with characteristics of the electoral environment (i.e. partisan conflict and issue salience), the current design does not allow me to control for other national-level characteristics. For example, a recent study using a multi-level approach to explain variation in economic voting demonstrates the importance of party system characteristics [START_REF] Duch | Context and the Economic Vote: A Multi-Level Analysis[END_REF]. Could this also be the case for EU issue voting? Future research into EU issue voting should try to examine the multi-level nature of the EU issue voting process and, if data availability allows, by using multi-level analysis techniques. Secondly, a comprehensive understanding of EU issue voting requires one to disaggregate country patterns to discern fine-grained patterns. Hence, in future research it will be important to investigate variation in EU issue voting across parties and voters. Finally, I have suggested that the key to understanding why conflict and salience vary may lie in the extent to which Eurosceptic political entrepreneurs on the right and left extremes mobilize the EU issue. Preliminary results support this viewpoint, but they need to be confirmed in future research. For now, the findings lend credence to Van der Eijk and Franklin's idea that the sleeping giant of Euroscepticism may be woken up by political entrepreneurs. I suspect the princes to be of radical left or radical right lineage.

Notes

I am grateful to the Danish Data Archive, the Dutch Data Archiving and Networking Services, the Zentral Archiv für Empirische Sozialforschung and the UK Data Archive for making available the data used in this study. I am also indebted to Harmen Binnema, Erica Edwards, Lawrence Ezrow, Liesbet Hooghe, Seth Jolly, Gary Marks, Marco Steenbergen, Barbara Vis, Tijmen de Vries and three anonymous reviewers as well as the editor of EUP for their insightful comments on earlier drafts of this article. Remaining errors are my sole responsibility.

1 In her work on the electoral success of niche parties, Bonnie [START_REF] Meguid | Competition between Unequals: The Role of Mainstream Party Strategy and Niche Party Success[END_REF] also highlights the importance of partisan conflict and issue salience. She argues that niche parties (i.e. green and far right) are more likely to be electorally successful when mainstream parties engage them on their favourite policy issue and, by doing so, presumably increase its salience, and when they take competing positions on this issue. [START_REF] Adams | Abortion: Evidence of an Issue Evolution[END_REF]and 2001UK data, the 1994, 1998and 2001Danish data, the 1994, 1998and 2002Dutch data and the 1998and 2002 German data and found that these measures correlate at the .80 level or higher (for a more in-depth cross-validation of voters' and experts' judgements of EU party positioning, see [START_REF] Marks | Cross-Validating Data on Party Positioning on European Integration[END_REF]. 4 One potential problem with a conditional logit model is the independence of irrelevant alternatives (IIA) assumption. IIA means that the ratio of the choice probabilities for two alternatives, A and B, is independent from all other alternatives in the choice set (see [START_REF] Agresti | Categorical Data Analysis[END_REF]. I computed a Hausman test statistic for the respective elections, which demonstrated that the IIA assumption seems reasonable. 5 This expectation builds on the proximity model developed by [START_REF] Enelow | The Spatial Theory of Voting: An Introduction[END_REF]. This model assumes that voters act rationally and vote on the basis of policy outcomes that they associate with the future government. An alternative conceptualization of issue voting is the directional voting model by [START_REF] Rabinowitz | A Directional Theory of Issue Voting[END_REF], who include direction and intensity in conceptualizing the distance between voters and parties. Since not all election studies provide the information needed to construct distances on the basis of the directional model, I use the proximity model. 6 I use voters' and parties' placements on nuclear energy in German and Dutch surveys to tap into the environment issue. The original coding of voter and party placements on the EU, immigration and environment issue in the Dutch and German election studies was based on a 7-point scale. In order to guarantee comparability across the different countries, these items were recoded to a 5-point scale. The original 10-point scales of left/right voter and party placements for the UK, Danish, Dutch and German studies were collapsed into a 5-point scale. Different permutations of rescaling do not affect the results. 7 The web appendix is available at http://www.uni-konstanz.de/eup/ issues.htm. 8 The odds ratio is defined as exp(b); see [START_REF] Agresti | Categorical Data Analysis[END_REF]. 9 There is no evidence of multicollinearity. I calculated the variance inflation factors (VIF) for the several analyses. First, I performed auxiliary regressions, then I computed the separate VIF scores using the following formula: 1/(1 -R 2 ). The VIF scores are below 1.23 (the VIF for the conditional logit regression model of the 2001 Danish election was the highest at 1.23). This finding is in line with correlation analyses, which demonstrated that the correlations between the predictors were well below .30, which is clearly below the critical value of .80.

  level of education (1 = high; 0 = low).

Figure 1

 1 Figure 1 EU issue salience. Notes: Question wording used: 'What is the most important problem facing the nation today?' Values indicate the percentage of voters indicating that issues regarding European integration or the euro constitute the most important problem facing their country. Sources: National election surveys.

Figure 2

 2 Figure 2 EU issue salience of Eurosceptic extremist parties. Notes: Question wording used: 'What is the relative importance of the European integration issue in the party's [list of parties] public stance in [year]?' Issue salience ranges from 1 = low to 5 = high. List of parties: EL: Enhedslisten (Unity List); SF: Socialistisk Folkeparti (Socialist People's Party); FrP: Fremskridtspartiet (Progress Party); DF: Dansk Folkeparti (Danish People's Party); CON: Conservative Party; PDS: Partei des Demokratischen Sozialismus (Party of Democratic Socialism); LPF: Lijst Pim Fortuyn (List Pim Fortuyn); SP: Socialistische Parij (Socialist Party). Source: Chapel Hill Expert Survey on party positioning regarding European integration, 1992-2002.

Table 1

 1 Description of dependent and independent variables

Table 2

 2 Partisan conflict on left/right and pro-/anti-EU dimensions

			Party	Party
		Election	dispersion on dispersion on Ratio
	Country	year	left/right	pro-/anti-EU	measure
	Denmark	1994	0.92	0.94	1.02
		1998	0.80	1.08	1.35
		2001	0.73	1.00	1.37
	Germany	1998	0.81	0.43	0.53
		2002	0.90	0.46	0.51
	Netherlands	1994	0.74	0.25	0.33
		1998	0.65	0.21	0.32
		2002	0.64	0.50	0.78
	United Kingdom	1992	0.76	0.76	1.00
		1997	0.72	1.10	1.52
		2001	0.60	1.15	2.65
	Notes: The ratio measure is constructed by dividing the party dispersion on the pro-/anti-EU

dimension by the party dispersion on left/right. Values of 1 and above indicate high partisan conflict, whereas a value below 1 signifies low partisan conflict on the EU dimension. Source: National election surveys.

Table 3

 3 Conditional logit estimates

	Denmark

  2 The 1994 German election and the 2003 Dutch election could not be added to the analysis, because these election surveys do not contain questions regarding EU issues. The analysis presented in this article is based on data from the following surveys: 1. Nationaal Kiezersonderzoek 1994, primary investigators: Kees Aarts, Hans Anker, Joop van Holsteyn, Erik Oppenhuis, Valgundersøgelsen 1998, primary investigators: Jørgen Goul Andersen, Johannes Andersen, Ole Borre and Hans Jørgen Nielsen, DDA-4189, Odense, Danish Data Archive, 1999; 6. Valgundersøgelsen 2001, primary investigators: Jørgen Goul Andersen, Ole Borre, Hans Jørgen Nielsen, Johannes Andersen, Søren Risbjerg, Jacques Thomassen and Jørgen Elklit, DDA-12516, Odense, Danish Data Archive, 2003; 7. Politische Einstellungen, politische Partizipation und Wählerverhalten im vereinigten Deutschland 1998, primary investigators: Oscar W. Gabriel, Jurgen W. Falter and Hans Rattinger, ZA-3066, Zentral Archiv für Empirische Sozialforschung, 1998; 8. Politische Einstellungen, politische Partizipation und Wählerverhalten im vereinigten Deutschland 2002, primary investigators: Oscar W. Gabriel, Jurgen W. Falter and Hans Rattinger, ZA-3861, Zentral Archiv für Empirische Sozialforschung, 2002; 9. British General Election Study 1992, primary investigators: Anthony Heath, Roger Jowell, John K. Curtice, Jack A. Brand and James C. Mitchell, SN 2981, UK Data Archive, 1993; 10. British General Election Study 1997, primary investigators: Anthony Heath, Roger Jowell, John K. Curtice and Pippa Norris, SN 3887, UK Data Archive, 1999; 11. British General Election Study 2001, primary investigators: Howard Clark, David Sanders, Marianne Stewart and Paul F. Whiteley, SN 4619, UK Data Archive, 2003. 3 The Chapel Hill expert survey data on party positioning on European integration are downloadable from: http://www.unc.edu/%7Ehooghe/ parties.htm. I cross-validated the voters' and experts' judgements of party positions on an EU scale for the

	Paul Pennings and Karin Wittebrood, P1209, Steinmetz Archief, 1995;
	2. Nationaal Kiezersonderzoek 1998, primary investigators: Kees Aarts, Henk
	Van der Kolk and Jacques Thomassen, P1415, Steinmetz Archief, 1999;
	3. Nationaal Kiezersonderzoek 2002, primary investigators: Galen A. Irwin,
	Joop J.M. Van Holsteyn and Josje M. Den Ridder, P1628, Steinmetz Archief,
	2004; 4. Valgundersøgelsen 1994, primary investigators: Jørgen Goul
	Andersen and Ole Borre, DDA-2210, Odense, Danish Data Archive, 2002;
	5.

European Union Politics 8(3)

de Vries Sleeping Giant: Fact or Fairytale?