Public opinion is increasingly at the heart of both political and scholarly debates on European integration. This article reviews the large literature on public support for, and opposition to, European integration, focusing on conceptualization, causes, and consequences: What is public support for European integration? How can we explain variation in support and Euroskepticism? What are the consequences of public support for elections and policy making in the European Union? The review reveals that although a growing literature has sought to explain individual support for European integration, more work is needed to understand the ways in which opinions are shaped by their national context and how increasing public contestation of the European Union poses a challenge to, and an opportunity for, the future of the integration project.

The European Union (EU) is facing one of the rockiest periods in its existence. At no time in its history has it looked so economically fragile, so insecure about how to protect its borders, so divided over how to tackle the crisis of legitimacy facing its institutions, and so under assault by Eurosceptic parties. The unprecedented levels of integration in recent decades have led to increased public contestation, yet at the same the EU is more reliant on public support for its continued legitimacy than ever before. This book examines the role of public opinion in the European integration process. It develops a novel theory of public opinion that stresses the deep interconnectedness between people’s views about European and national politics. It suggests that public opinion cannot simply be characterized as either Eurosceptic or not, but rather that it consists of different types. This is important because these types coincide with fundamentally different views about the way the EU should be reformed and which policy priorities should be pursued. These types also have very different consequences for behaviour in elections and referendums. Euroscepticism is such a diverse phenomenon because the Eurozone crisis has exacerbated the structural imbalances within the EU. As the economic and political fates of member states have diverged, people’s experiences with and evaluations of the EU and national political systems have also grown further apart. The heterogeneity in public preferences that this book has uncovered makes a one-size-fits-all approach to addressing Euroscepticism unlikely to be successful.

Do political parties respond to shifts in the preferences of their supporters, which we label the partisan constituency model, or to shifts in the mean voter position (the general electorate model)? Cross-national analyses — based on observations from Eurobarometer surveys and parties’ policy programmes in 15 countries from 1973 to 2002 — suggest that the general electorate model characterizes the policy shifts of mainstream parties. Alternatively, when we analyse the policy shifts of Communist, Green and extreme Nationalist parties (i.e. ‘niche’ parties), we find that these parties respond to shifts in the mean position of their supporters. The findings have implications for spatial theories and political representation.

Theories of issue evolution and issue manipulation suggest that ‘political losers’ in the party system can advance their position by introducing a new issue dimension. According to these theories, a strategy of issue entrepreneurship, that is the attempt to restructure political competition by mobilizing a previously non-salient issue dimension, allows political losers to attract new voters and reap electoral gains. In this study, we examine the extent to which these expectations hold by exploring issue entrepreneurial strategies of political parties when applied to the issue of European integration. Using multi-level modelling to analyse European Election Study data, we first show that voters are more likely to cast their ballot for parties that are losers on the extant dimension based on concerns related to European integration. Secondly, a time-series cross-sectional analysis demonstrates that parties that employ an issue entrepreneurial strategy are more successful electorally. Put differently, voters are responsive to the issue entrepreneurial strategies of parties. These findings have important implications for our understanding of party competition and electoral behaviour in multi-party systems.