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.
1997 Mexican legislative election
Legislative elections were held in Mexico on 6 July 1997. The Institutional Revolutionary Party won 239 of the 500 seats in the Chamber of Deputies, the first time it had failed to win a majority. As a result, the leaders of the Party of the Democratic Revolution and of the National Action Party were able to control Congress and installed PRD member Porfirio Muñoz Ledo as the president of the Chamber of Deputies. At first, the PRI refused to accept the nomination and its parliamentary leader, Arturo Núñez Jiménez, declared it illegal. However, the PRI later accepted the fact and Muñoz Ledo answered the state of the union address of President Ernesto Zedillo.