Decomposition of Regional Voting in South Korea

In this article, I offer a theoretical model specifying the electoral mechanism in South Korea. In the model, political parties offer regional benefits to sway the ideological voting decisions of voters. Regional benefits are an effective way of winning regional votes as the parties’ ideological positions become less distinguishable. Analysis of the model shows that political parties receive stronger regional support (1) as the ideological positions of voters and their regional party become more congruent and (2) when voters have a powerful regional leader. I test these predictions using two statistical models - one based on survey data the other on aggregate election outcome data. The results indicate that previous interpretations of regional voting in terms of either ideological conflicts or regional nepotism overestimate the effects of these factors.