Dominance by a single party can deteriorate the quality of political representation. Yet, surprisingly, voters sometimes support a formerly dominant party they had previously thrown out of power. As an important case, this essay studies the victory in the 2012 elections in Mexico of the Institutional Revolutionary Party (PRI). Why did voters give it a new opportunity to rule the country? Accusations of fraud have been insufficient to explain the party’s victory, so this research looks for electoral explanations. The paper points to fatigue with the incumbent party; unsatisfying economic and security conditions; ineffective campaigns by both the National Action Party (PAN) and the Party of the Democratic Revolution (PRD); the PRI’s popularity based on its governing experience; and a convincing PRI candidate who secured the conservative, rural, and poor voters. This conveys the mandate for Peña Nieto to produce tangible results without abandoning democracy. More broadly, these observations shed light on the perplexing phenomenon of formerly dominant parties making an electoral comeback.