Why rules matter: Changes in candidate selection in Mexico's PRI, 1988-2000

The traditional literature on Mexico's formerly hegemonic party, the PRI, n otes the importance of the 'informal rules of the game' in determining outc omes, such as who will be the PRI's presidential candidate. This article ar gues that the onset of electoral competition allowed weaker actors within t he party to strengthen their position by reforming the statutes in order to give them decision-making power previously denied them. However, this was a difficult process. President Salinas was able to overturn statutory refor ms, while President Zedillo was not. Now that the PRI has lost the presiden tial elections, internal mechanisms of distributing selective benefits beco me even more important because of the loss of the omnipotent president who once exacted cooperation from all actors within the party and the regime.