A vast literature studies the effects of electoral institutions on party systems. Research on the relationship between electoral systems and the strength of partisan identities, however, is inconclusive, as existing work mostly focuses on individual-level factors such as political sophistication and attitudinal variables.
In this paper, Diego analyses the case of Indonesia to illustrate a close link between electoral laws and patterns of mass partisanship. By exploiting variation over time (four electoral cycles), he argues that deep-seated partisan affiliations weakened substantially with the introduction of open-list PR, a system that provides strong incentives to cultivate the personal vote.
By analysing variation across space (138 districts), he further documents that this process of partisan dealignment has been more pronounced in districts in which clientelistic practices are widespread. These findings suggest that electoral institutions are a powerful driver of partisan identities and that the effect of institutional change at the national level may be contingent on local politics.