Making up one’s Political Mind. Party Cues vs. Self-Persuasion in the Brexit Referendum

A growing strand of the political behavior literature focuses on the role of information during election and referendum campaigns. Voters are acting within information environments shaped by political actors – such as candidates, political parties, social movements, interest associations - and the media, both old and new. Numerous studies show that in particular political parties play a crucial role, providing voters with important cues in the opinion formation process. At the same time, a growing literature in political psychology points to cognition, persuasion, perceptions etc. as mechanisms impacting on voters during electoral campaigns. Our paper will bring these two strands together. More precisely, we measure the impact of party cues on vote intention as well as on vote decision in the recent referendum process on Brexit in the United Kingdom. In parallel, we will measure how revealed attitude aggregation, in a specifically programmed voting advice application, impacts through the mechanism of self-persuasion on the same two outcome variables. Thanks to the experimental set-up of the study (we commissioned a series of survey experiments with representative samples of the UK electorate) and novel data stemming from three waves of interviews, we can show the causal, complementary effect of party recommendations and of voting advice application-generated information on individual level vote intention and vote choice. We thus advance our theoretical knowledge on public opinion formation, coupled with a solid experimental research design allowing us to make a series of important causal claims.