Cárdenas and Muñoz Ledo created a pact in 1988 with the Mexican left in which the Mexican Socialist Party ( whose candidate was Heberto Castillo ) decided to support Cárdenas ' candidacy as well . Also , the alliance with social organizations was obtained , like the Coalition of Workers , Peasants , and Students of the Isthmus ( COCEI ) ( that had gained the local elections in Juchitán de Zaragoza ) , the Independent Central of Agricultural Workers and Peasants ( CIOAC ) , the Assembly of Districts of the City of Mexico ( created after 1985 earthquakes ) , the Union of Popular Colonies and the Revolutionary Union of Emiliano Zapata , among others . This agglomerate of civil parties and organizations they would be , along with the Democratic Current of the PRI , the base of future PRD
1985 earthquakes
1985 Mexico City earthquake
National Democratic Front (Mexico)