June 7, 2015 Held


United Mexican States

Election for Camara de Diputados (Chamber of Deputies)


Cast Votes:39,872,757
Valid Votes:37,971,876
Invalid Votes:1,900,881


Party Seats Won Seats Change Votes

Institutional Revolutionary Party 203 - 11,638,675


National Action Party 108 - 8,379,502


Party of the Democratic Revolution 56 - 4,335,745


Morena 35 - 3,346,349


Green Ecological Party of Mexico 47 - 2,758,152


Citizen Movement 26 - 2,431,923


New Alliance Party 10 - 1,486,952


Social Encounter Party 8 - 1,325,344


Labour Party 6 - 1,134,447


Humanist Party None 856,903


Independents 1 - 225,500


More Info:

At stake in this election:      

  • The 500 seats in the Chamber of Deputies (Cámara de Diputados)

Description of government structure:

  • Chief of State: President Enrique PEÑA NIETO
  • Head of Government: President Enrique PEÑA NIETO
  • Assembly: Mexico has a bicameral National Congress (Congreso de la Unión) consisting of the Senate (Cámara de Senadores) with 128 seats and the Chamber of Deputies (Cámara de Diputados) with 500 seats.

Description of electoral system:

  • The President is elected by plurality vote to serve a 6-year term.
  • In the Senate (Cámara de Senadores), 96 members are elected by plurality vote in multi-member constituencies to serve 6-year terms and 32 members are elected through a closed-list proportional representation system to serve 6-year terms*. In the Chamber of Deputies (Cámara de Diputados), 300 members are elected by plurality vote in single-member constituencies to serve 3-year terms and 200 members are elected through a closed-list proportional representation system to serve 3-year terms.**

* The voter votes at the state level. 96 Senators are elected from closed party lists in 32 districts of three seats, each corresponding to a state. The top vote-getting list wins two seats. The next-placed list wins one. Parties may nominate two candidates in any given district. 32 more Senators are elected from closed, nation-wide party lists. National vote shares are determined by summing state-level results. The threshold in this tier was two percent in 2012, but will increase to three percent in 2018.

** The voter casts one vote at the single-member district level. PR seats are allocated from closed lists in five multi-member districts of 40 seats each in order to make each party's seat share proportional to its vote share at the MMD level. No party may seat more than 300 deputies. No party's seat share may be more than eight percent in excess of its vote share. This rule does not hold, however, if the disproportion results in the single-member district tier. A party may not contest seats in the proportional tier unless it registers candidates in at least 200 single-member constituencies. The threshold in the proportional tier is three percent.

Main parties in the electoral race[1]:

*Convergence / Convergencia (PC) was renamed the Citizens’ Movement / Movimiento Ciudadano in 2011. 

** These political parties obtained their registry in early 2014, and this election will not only be their first competition, but if they fail to obtain at least 3% of the votes, will lose their registration and will not be able to present candidates in the presidential elections of 2018.

Last election:

  • The last election for the Chamber of Deputies (Cámara de Diputados) was held on 12 July 2012.  There were 79,454,802 registered voters for the election.  The National Action Party / Partido Acción Nacional (PAN) won 114 seats, the Institutional Revolutionary Party / Partido Revolucionario Institucional (PRI) won 207 seats, the Party of the Democratic Revolution / Partido de la Revolucion Democratica (PRD) won 100 seats, the Labor Party / Partido del Trabajo (PT) won 19 seats, the Green Ecological Party of Mexico / Partido Verde Ecologista de México (PVEM) won 34 seats, the Convergence / Convergencia (PC) won 16 seats, and the New Alliance Party / Partido Nueva Alianza (PANAL) won 10 seats. 

Population and number of registered voters:

  • Population: 120,286,655 (2014 est.)[2]
  • Registered Voters: 83,563,272 (2015)[3]*

* Includes all citizens, as of April 24, who applied for registration and already have the necessary photo identification.  When all Mexican citizens who applied for registration are counted (including those without photo identification), the total number of registered voters is 87,244,970. 

Gender Data:

  • Female Population: 61,267,845 (2014 est.)[4]
  • Is Mexico a signatory to CEDAW: Yes (17 July 1980)
  • Has Mexico ratified CEDAW: Yes (23 March 1981)[5]
  • Gender Quota: Yes
  • Female Candidates in this election: Yes
  • Number of Female Legislators: 184 (37%) of 500 seats in the Chamber of Deputies (Cámara de Diputados)[6]
  • Human Development Index (HDI) Position: 71[7]
  • Social Institutions and Gender Index (SIGI) Categorization: N/A[8]

Disability Data:

  • Is Mexico a signatory to CRPD: Yes (30 March 2007)
  • Has Mexico ratified CRPD: Yes (17 December 2007)[9]