Despite existing literature that often conflates the terms party membership and party activism, the first is a formal ascription with a given party organization, while the second entails a set of practices, whether sporadic, informal, or devoted, that (a group of) individuals perform to support a political party either during an electoral campaign or more permanently, independently of being enrolled in the party or not. Party members and activists can be analyzed from both the normative model of democracy and the inner functioning of political parties. Focusing on Latin America, party membership and party activism are related to various types of party organizations, social cleavages, and party identification. Individuals join, and/or work for, parties to gain tangible benefits, information, social advantages, and influence, as well as mental satisfaction, without which they could lose financial resources, time, and alternative opportunities. Moreover, prior contributions on party membership and activism based on Latin American countries has emphasized the functions party supporters have as connectors between the citizenry and the party organizations. In this regard, scholars conceive members’ participation not only as a mechanism for party rootedness (“vertical” function), but also as a connection between social and partisan arenas (“horizontal” function). In the region, the research area of party membership and activism portrays virtues and limitations in methodological terms both at the aggregate and the individual level. As a future research agenda, party membership and activism in Latin America should be further studied using comparative strategies, avoiding the pitfalls of public opinion research, not to mention making additional efforts to keep the two terms conceptually distinct. Also, party members and activists can be explored in transnational perspective, joining forces with the blooming literature of political party abroad.
