More than thirty years after the onset of Latin America’s “third wave” of democratization, the fragility of partisanship in the region remains a major puzzle. This fragility is especially puzzling when new democratic regimes have proven to be far more durable than anyone could have imagined when the third wave began (Mainwaring and Pérez-Liñán 2005). Historically, the oscillation between democratic and authoritarian regimes interfered with the institutionalization of party systems in the region (Lupu and Stokes 2010). Authoritarian rule led to frequent proscriptions or repression of specific party organizations (especially populist or leftist parties with working-class constituencies), as well as prolonged interruptions in electoral competition that disrupted parties’ efforts to recruit members, organize local branches, and construct collective identities. Consequently, as new democratic regimes demonstrated a surprising ability to withstand the region-wide economic crisis of the 1980s, scholars expressed optimism that party systems would institutionalize alongside them (Dix 1992).

In much (though not all) of the region, this institutionalization did not occur. Democratic regimes gradually consolidated and economies eventually recovered from the debt crisis and hyperinflation, but party systems, on average, did not become more electorally stable. To the contrary, they actually became progressively less stable during the first three decades of the third wave. Simply put, regular electoral competition did not institutionalize party systems as representative bodies or intermediaries between citizens and states.