Institutional Revolutionary Party
The Institutional Revolutionary Party (, PRI) is a Mexican political party founded in 1929 that held uninterrupted power in the country for 71 years from 1929 to 2000, first as the National Revolutionary Party (, PNR), then as the Party of the Mexican Revolution (, PRM), and finally renaming itself as the Institutional Revolutionary Party in 1946.
Mexican Workers' Party
In 1987, in an effort to unify the different leftist forces in Mexico, the PMT and the Unified Socialist Party of Mexico fused and created the new Mexican Socialist Party, which two years later would be the main origin of the Party of the Democratic Revolution.