My dissertation book project explains the divergent trajectories of three contemporary populist leaders in Latin America: Nayib Bukele in El Salvador, Andrés Manuel López Obrador in Mexico, and Jair Bolsonaro in Brazil. It argues that the combination of the insider advantage and federalism explain these leaders’ trajectories. In El Salvador, Bukele had the insider advantage and operated in a centralized system, which enabled him to consolidate the loyalty of voters and elites and swiftly take over institutions, leading to a personalistic hegemony. In Mexico, AMLO also had the insider advantage, which gave him a strong voter base, but federalism reduced elite loyalty and slowed the takeover, pushing him toward a party-based hegemony. In Brazil, Bolsonaro lacked the insider advantage and faced the constraints of a federal system, which weakened both voter and elite loyalty, culminating in his electoral defeat after one term.