The party (un)faithful: Explaining party members’ defecting voting behaviour in different contexts (Belgium and Britain)

Abstract

Party members are often depicted as loyal voters that supply the party with a small but steady electoral base. Research, however, suggests that party members occasionally vote for other parties in general elections. This might either be a strategic choice or an indication of their discontent, possibly preceding a choice to exit the party. Using original survey data on more than 9000 party members in Flanders (Belgium) and Britain, this article aims to extend our understanding of why party members defect. We test hypotheses that take into account both individual and party-level considerations (ideological concerns, leadership evaluations and strategic choices) and the conditioning effects of party and electoral systems. Our analysis shows that institutional settings are crucial for strategic voting, whereas ideological concerns and leadership evaluations matter equally in both countries. As such, our study provides important insights in the attitudes and behaviour of party members, contributing to current debates on the contemporary meaning of party membership.