Multiple Partisan Identities and their Impact on Voting Decisions

The concept of party identification as originally developed in the United States allows voters to identify either as a Democrat or as a Republican, but not with both parties. In a two-party system, there are good reasons to adhere to this view. However, several scholars have argued that in multi-party systems the situation is fundamentally different. One of the reasons that partisan identities in such systems tend to be less stable, is the presumed possibility of multiple party identification. In this paper, we take up this issue and analyse this with a multi-item index of partisan identities, which we have recently validated in several countries (Bankert, Huddy & Rosema, 2016). More specifically, using data from Sweden and the Netherlands, we analyse to what extent voters identify with more than one political party and what factors have an impact on the existence and structure of such attachments. Furthermore, we analyse their impact on the moment of voting decisions as well as party choice. The findings have important implications for the conceptualization as well as measurement of partisan identities in multi-party systems and for models of voter decision making.