This chapter analyzes the case of the Frente Amplio (Broad Front, FA) in Uruguay as an unusual organization. Since its founding, the FA has exhibited a dual structure: a coalition of various factions that compose the party and a movement comprising a common grassroots structure (Base Committees). The latter is not necessarily affiliated with any particular faction and it participates in all of the party’s decision-making structures. The FA fulfills the essential functions required to qualify as a political party. These functions manifest themselves in the participatory processes that develop the party’s electoral platforms and also control the nomination of presidential candidates. More critically, the coalition and the grassroots movement tended to influence the policy decisions of the party’s parliamentary caucus when the FA was an opposition party, as well as the decisions of the executive branch when the FA was in government (2005–20). In this process, grassroots party activists exercised significant influence over political decisions that were particularly sensitive for the Left. Regarding vertical interest aggregation, the FA has developed strong, informal links with various social actors, especially with labor unions.

The FA, like every political party organization in a democratic context, has a tension between choosing policies and candidates that are closer to the preferences of the median voter versus those that are closer to members´ preferences. This chapter analyzes the role that the organizational structure exerts over the party in opposition and the party in government. The chapter presents observational evidence concerning the influence of the party on crucial policy issues and on the government’s decision-making. Also, it briefly details the process of ideological transformation of the FA. The chapter shows that the FA organizational structure limits the leaders’ and government’s room to maneuver. It limits party leaders´ incentives to moderate their positions because major decisions need to have the organization´s explicit support, or at least an absence of opposition. When the FA is in government, the party organization also constrains government action concerning substantive and crucial policy issues. The lesson from the analysis in this chapter is that the party´s organizational structure can present challenges for strategic adaptation but provides insurance against the risk of brand dilution.

This chapter uses process tracing to argue that organizations that grant voice and veto power to activists in the decision-making process avoid oligarchization of the party. The FA presents an opportunity to analyze how party organization per se affects the performance of political parties. The FA is a successful case of party building and reproduction that sheds light on the role organizational structure plays in reproducing activists. The process tracing systematically describes and explains the formation and reproduction of the party. It shows how the party´s first steps as a political organization established a reproduction mechanism with a lock-in effect that explains the persistence of the party’s activism.

The professionalization of politics and the disappearance of party organizations based on activists seems an inescapable trend. This chapter shows the relevance of organizational rules for explaining the reproduction of party activism. Using data from both an online survey of people differing in their levels of engagement with the FA and in-depth interviews with party activists, we show that those with relatively low levels of engagement – “adherents” – and activists differ in their willingness to cooperate with the party and in the amount of time they devote to party activities. Also, we find that reducing the perceived efficacy of political engagement strongly decreases activists’ self-reported willingness to engage with the party, while this reduction has no effect upon adherents. These findings suggest that the design of organizational rules that grant a political role to grassroots organizers can promote party activism.

The chapter presents the setting in which the FA was born and in which it developed over the years. The combination of the exhaustion of the ISI model, increasing political polarization and the height of the Cold War dramatically determined the political dynamics of the late 1960s and 1970s and engendered a context of increasing authoritarianism and political violence. The fight against increasingly repressive governments was a significant incentive for the new party. Public opposition to the neoliberal agenda of the different governments that succeeded the authoritarian regime (1971–1985) also contributed to the FA’s increasingly successful electoral. In 2005, the FA gained office and won three consecutive national elections with an absolute majority in parliament. It was one of the most successful parties of the so-called “left turn.” During its time in government, the party enacted structural reforms in various policy areas. In terms of socioeconomic reforms, the FA approved a tax reform, a health-care reform, and was one of the two parties of the “left turn” that enacted deep labor market reforms. The FA also pursued a distinctive progressive agenda in the region that led to the legalization of abortion, same-sex marriage, and the liberalization of cannabis use.

There have been other mass-organic parties in Latin America. This chapter discusses the FA case in comparative perspective. The literature has emphasized the role of exogenous factors or the ability of party leaders to strategically “adapt” to explain the transformation of formerly mass-organic parties. The case of the FA, which confronted similar exogenous challenges, calls attention to the relevance of organizational structure in determining party activists’ level of engagement. Organizational design is crucial for fostering and reproducing activism. The chapter reviews the case of the Partido dos Trabalhadores (PT) in Brazil, a former mass-organic leftist party that turned into a professional–electoral party. The PT is the case that most closely resembles the FA in its emphasis on grassroots activism. The comparison with the PT, as a negative case, increases the theory’s analytical leverage. Second, the chapter discusses the case of the FA as a strange electoral alliance or coalition. It compares the case of the FA with other leftist coalitions in Latin America, with a special focus on the experiences of leftist coalitions in Chile, showing that the FA developed a distinctive, shared organizational structure that is not observable in other, similar electoral alliances.

This chapter describes grassroots activism and the FA’s peculiar organizational structure in which 7,000 grassroots activists have a significant autonomous voice in the FA decision-making bodies. Grassroots activists’ participation in the FA occurs in Base Committees (the movement) and in the different FA factions (the coalition), two different avenues of engagement with the FA. In the former, there is no direct control of factions, leaders, or party elites because Base Committees are not involved in candidate selection. The chapter provides a thick description of the party´s structure and shows the relevance of activism in the FA and its interaction with leaders and factions in party life.

Uruguay’s Frente Amplio (Broad Front, FA) is a mass-organic institutionalized leftist party. It is a deviant case that helps explicate the reproduction of mass-organic party organization and activism. The peculiar internal structure of the FA and the rules that ensure a role for grassroots activists in the highest decision-making bodies of the party are a product of the extraordinary conditions that existed at the time of the party’s birth in 1971. The intense autonomous activism that occurred during this stage acts as a historical cause. The decision-making authority of the grassroots activists, granted incrementally since the FA’s foundational stage, enables activists to block changes that reduce their power, engendering a lock-in effect and positive feedback. These rules grant FA activists a significant voice, which imbues activists´ participation with a strong sense of efficacy. This perceived efficacy operates as a selective incentive for activists to engage with the party. The chapter develops this theoretical argument and justifies the selection of the FA as a deviant case of party reproduction.