Abstract:  This article maps in a comprehensive way the relationships between support for European integration, left–right ideological positions, and policy attitudes towards redistribution, immigration, and gay rights. I introduce the use of flexible non-parametric methods (generalized additive models) and more appropriate measures of dependence (the distance correlation coefficient) to explore and measure the strength and forms of these relationships across time (2004–2023), countries, and indicators of European integration support. The link between European integration attitudes and left–right ideology is weak. The exact form of the relationship depends on the operationalization of EU attitudes, country, and time period, but it rarely resembles the classic inverted-U curve suggested by existing literature and studies of party positions. In fact, average EU support is typically highest at the moderate left rather than at the center. The relationship of European integration attitudes with immigration positions is much stronger, stable, consistent, and almost linear; with support for gay rights it is also linear but considerably weaker; with support for redistribution there is practically no relationship at all. While public opinion is much less structured and less extreme than party positions, there is some evidence that—across countries—the strength of the links between EU attitudes, left–right ideology, and policy positions at the party level is associated with the strength of these links at the level of the public. Furthermore, over time the strength of the link between European integration attitudes and different policy attitudes covaries systematically with the salience (media presence) of the policy issue at the EU level.

Keywords:  European integration; ideology; left–right; party positions; political attitudes; public opinion

Published:   Ahead of Print

Issue:   Vol 14 (2026): Consensus About the European Union? Understanding the Views of Citizens and Political Parties (In Progress)