Introduction

During the third wave, like most democratizing countries worldwide, Latin American countries replaced plurality rules for presidential election with runoff rules. To date, most scholars fear the proliferation of political parties under runoff and favor plurality. I argue, however, that Latin American leaders were correct to adopt runoff. Runoff established a virtuous circle: amid lower barriers to entry, opposition parties and new parties held greater respect for the democratic process and this respect was in turn important to elites’ toleration of their entry. By contrast, plurality often facilitated political exclusion by long-standing dominant parties and exacerbated cynicism and polarization. Although the larger number of parties under runoff was problematic, and measures for the amelioration of the problem are important, the number of parties was considerable under plurality; runoff enabled democracies to cope, increasing the legitimacy of their elected presidents.