How do Latin America’s poorest citizens participate in politics? This article explores the role that community organizations play in mobilizing individuals into three common modes of political participation: voting, protesting, and contacting government. It argues that community organizations help mobilize poor individuals both through the resources they provide for mobilization and because they serve as sites where political parties target individuals for mobilization. It analyzes survey data from LAPOP surveys for 18 Latin American countries and finds that overall, poor people are just as politically active as more affluent individuals; that involvement in community organizations is a very strong predictor of all types of political participation; and that membership in organizations has an especially strong effect on voting and protesting for poor people. By equalizing levels of political participation across income groups, organizations help erase class-based inequalities in participation that have plagued democracies in the region.