Party Dominance and the Logic of Electoral Design in Mexico's Transition to Democracy

In: Journal of theoretical politics, Band 13, Heft 3, S. 271-293

Abstract

This paper discusses the role of electoral institutional design in Mexico's transition to democracy. Our argument is that electoral rules facilitated party dominance through two mechanisms: electoral rules disproportionately rewarded existing majorities and, at the same time, discouraged potential majorities from forming. More specifically, the rules rewarded parties that could win a majority of the vote in single-member districts; but at the same time, rewarded minority parties with seats from multi-member districts, mitigating Duvergerian incentives to coordinate behind a single challenger. In the short run, seats from multi-member districts benefited opposition parties by significantly reducing entry costs; in the long run, however, these seats helped sustain party dominance, by discouraging coordination among opposition parties and voters.