1976 Mexican general election

Valentín Campa ran as a write-in candidate for the Mexican Communist Party.

Amidst a social and economic crisis, president Luis Echeverría appointed his finance minister, José López Portillo, as the candidate for the ruling PRI in the 1976 presidential elections. Before the electoral reform of 1977, only four political parties were allowed to participate in the elections: the ruling Institutional Revolutionary Party (PRI), the Popular Socialist Party (PPS), the Authentic Party of the Mexican Revolution (PARM) and the right-wing National Action Party (PAN), which was practically the only real opposition party at the time.[5]

The PPS and the PARM supported López Portillo's candidacy, as they had traditionally done with previous candidates for the PRI.

At the time, the opposition party PAN was going through internal conflicts and, for the first time upon its foundation, was unable to nominate a candidate for the 1976 presidential elections.

On the other hand, the Mexican Communist Party nominated Valentín Campa as their presidential candidate. At the time, however, this party had no official registry and was not allowed to participate in elections, so Campa's candidacy was not officially recognized and he didn't have access to the media. He had to run as a write-in candidate, as he would not appear in the ballots.[6]

These factors led to López Portillo effectively running unopposed. His campaign echoed this "unanimous" support for him, and his slogan was "La solución somos todos" ("All of us are the solution"). López Portillo later joked that, due to running without opposition, it would have been enough for "his mother's vote for him" to win the election.[7]

The elections took place during a tense period: the economic crisis, the leftist guerrilla sublevations in some parts of the country and the Dirty War the government took against them, were some of many factors that jeopardized the power of the ruling PRI.

There were many rumours that outgoing president Luis Echeverría was planning to carry out a coup d'état against his own candidate, López Portillo, to perpetuate himself in power. A month after the elections, a diplomatic cable sent by then American ambassador in Mexico, Joseph J. Jova, to the U.S. Department of State echoed those rumours, and detailed a hypothetical scenario in which Echeverría would order the assassination of president-elect López Portillo after September 1, using the leftist guerrilla Liga Comunista 23 de Septiembre and the CIA as scapegoats.[8] On August 13, the Liga tried to kidnap Margarita López Portillo, sister of the president elect; the attempt failed and the Liga's leader, David Jiménez Sarmiento, was killed by security forces during the incident.[9]

In the end, López Portillo took office as scheduled on December 1 without further incidents.

Although the results ensured the PRI remained in power, the lack of opposition to José López Portillo raised concerns about the lack of legitimacy of the Mexican political system[10][11]. 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.

These have been the last Mexican presidential elections in which a candidate has run unopposed.