The economic roots of cross-national similarity in voter preferences

We argue that economic and political integration leads voters' political preferences toward cross-national convergence. Analyzing data on voter preferences across 30 European democracies from 1976 to 2022, we measure the similarity of preference distributions across state dyads over time, documenting an average increase in similarity over this period. We then model these associations statistically and find that greater similarity and complementarity in economic production and co-participation in the European Union and the Eurozone are associated with increasingly similar voter preferences. The argument and analyses broaden our understanding of the political implications of globalization and also provide a theoretical and empirical foundation for two growing literatures: one on the cross-national diffusion of parties' strategies and one on the political implications of macroeconomic stimuli such as trade shocks or banking crises.