Whose election signaled the end of one-party rule in Mexico?

Vicente Fox Quesada [b. July 2, 1942] defeated the incumbent, Ernesto Zedillo Ponce de Leon [b. December 27, 1951], in the Mexican presidential election of July 2, 2000. He was the candidate of the National Action Party [Partido Accion Nacional, aka PAN], which had never had a successful nominee previously. In fact, no party other than the Institutional Revolutionary Party [Partido Revolucionario Institucional] had run a successful presidential campaign. For only PRI candidates had served presidential terms over the preceding 71 years.