General elections were held in Mexico on 4 July 1976.José López Portillo was the only candidate in the presidential election, and was elected unopposed. In the Chamber of Deputies election, the Institutional Revolutionary Party won 195 of the 237 seats, as well as winning all 64 seats in the Senate election. Voter turnout was 64.6% in the Senate election and 62.0% in the Chamber election.
Although the results ensured the PRI remained in power, in part due to the evident electoral fraud that took place, the lack of opposition to José López Portillo raised concerns about the lack of legitimacy of the Mexican political system. As a result, an electoral reform law was enacted in 1977, introducing partial proportional representation for the Congressional and Senate elections in order to ensure better representation of opposition parties – something extremely difficult under the first-past-the-post system that had been in force. However, the PRI retained its position as the dominant party, retaining the presidency until Vicente Fox of the National Action Party was elected in 2000.