Mainstream parties and the European integration of core state powers

Past research has shown that mainstream parties are overwhelmingly pro-European. But which kind of Europe do they prefer? The post-Maastricht integration of core state powers, and the crises it produced, has compelled mainstream parties to develop a clearer understanding of what the EU is and what it should be. We distinguish two such fundamental ideas of Europe: the redistributive polity, built on transnational solidarity, and the regulatory polity, built on national self-reliance. What determines mainstream parties’ support for either of these polity ideas? We investigate this question on data provided by the "EUandI" voting advice application, which contains hand-coded party positions on core issues of integration for all EU member states for the three EP elections since 2009. Mainstream party competition on European solidarity, we find, is mainly driven by their socio-cultural positioning, interacts with the salience of an issue in the national context, and plays out differently in the three macro-regions of the EU. Our findings show that, indeed, mainstream parties across the EU are generally supportive of integration. The substantive kind of Europe that they endorse, however, differs with their ideology, the salience of an issue, and regional circumstances.