 Historically, there were important high-profile defections from the Institutional Revolutionary Party, like the ones of Juan Andreu Almazán (1940), Ezequiel Padilla (1946), Miguel Henríquez Guzmán (1952), and Cuahtémoc Cárdenas (1988), son of President Lázaro Cárdenas.These departures happened mainly because they opposed the presidential candidate nominations; however, only Cárdenas departure in 1988 resulted in the establishment of another political party (Party of the Democratic Revolution).The presidential elections held in 1988 marked a watershed in Mexican politics, as they were the first serious threat to the party in power by an opposition candidate