# 2021 Mexican legislative election

Legislative elections were held in Mexico on 6 June 2021. Voters elected 500 deputies (300 in single-member constituencies by first-past-the-post and 200 by proportional representation) to sit in the Chamber of Deputies for the 65th Congress. These elections took place concurrently with the country's state elections.
On 5 December 2020 the National Action Party, the Institutional Revolutionary Party and the Party of the Democratic Revolution announced an electoral alliance, Va por México ("Go For Mexico"). Morena, the Labour Party and the Ecologist Green Party of Mexico formed the Juntos Hacemos Historia (″Together we make history″) coalition. Both alliances were approved by the National Electoral Institute (INE).
On 13 April 2021 the INE cancelled the registrations of Manuel Guillermo Chapman (Morena), Ana Elizabeth Ayala Leyva, (Juntos Haremos Historia), and Raúl Tadeo Nava (Labor Party) for failure to certify their lack of involvement in gender violence. On 3 June, the INE warned about possible sanctions on Catholic bishops, in particular Juan Sandoval Íñiguez, for their interference in the elections.
The elections were Mexico's largest in history and were tainted by several political assassinations and the COVID-19 pandemic in Mexico.

## Background
### COVID-19 pandemic

Several electoral events in 2020 were disrupted by the ongoing COVID-19 pandemic, leading to the postponement of the 2020 local elections from 7 June to 18 October. The National Electoral Institute (INE) implemented health protocols to mitigate the spread of the virus, which it later deemed successful.
On 3 February 2021, the INE stated that postponing the 2021 legislative election would not be advisable, with INE board president Lorenzo Córdova Vianello citing the effectiveness of the previously implemented sanitary measures. The institute also warned that a delay could trigger a constitutional crisis by preventing the timely installation of the 65th Congress.

## Electoral system

The National Electoral Institute (INE) oversees federal elections in Mexico. Its responsibilities include organizing election day logistics, producing and distributing electoral materials, counting votes, and certifying the election results.
Voters must present their voter ID at polling stations to cast their ballots.
On 28 April 2021, the INE announced that there were 93,528,473 registered voters in Mexico, 32,303 registered voters abroad, and 949 registered voters in preventive detention.

### Legislative election

The 500 members of the Chamber of Deputies are elected in two ways: 300 are elected in single-member constituencies by plurality vote, and the remaining 200 are elected by proportional representation in five multi-member districts, with seats divided according to Hamilton's method. No party is permitted to hold more than 300 seats. Deputies are elected for three-year terms and will serve in the 65th Congress.
For the first time since 1933, deputies elected for the 64th Congress in 2018 were eligible for immediate reelection due to the 2014 electoral reform.

## Political parties and coalitions

Ten national political parties were registered with the INE and were eligible to participate in federal elections: the National Action Party (PAN), the Institutional Revolutionary Party (PRI), the Party of the Democratic Revolution (PRD), the Labor Party (PT), the Ecologist Green Party of Mexico (PVEM), Citizens' Movement (MC), the National Regeneration Movement (Morena), the Solidarity Encounter Party (PES), Progressive Social Networks (RSP), and Force for Mexico (FXM).
The General Law of Political Parties stipulates that national political parties can form coalitions for elections by submitting a coalition agreement to the electoral authority. Parties cannot join coalitions in their first election. As the Solidarity Encounter Party (PES), Progressive Social Networks (RSP), and Force for Mexico (FXM) were newly established parties, they were not eligible for joining a coalition.
Parties that do not reach 3% of the popular vote lose their registration as a national political party.

### Summary

| Party or alliance | Party or alliance | Party or alliance | Leader | Position |
| Juntos Hacemos Historia | | National Regeneration Movement | Mario Delgado | Left-wing |
| Juntos Hacemos Historia | | Ecologist Green Party of Mexico | Karen Castrejón Trujillo | Centre-left |
| Juntos Hacemos Historia | | Labor Party | Alberto Anaya | Left-wing |
| Va por México | | National Action Party | Marko Cortés Mendoza | Centre-right to right-wing |
| Va por México | | Institutional Revolutionary Party | Alejandro Moreno Cárdenas | Centre or big tent |
| Va por México | | Party of the Democratic Revolution | Ángel Ávila Romero | Centre-left to left-wing |
| Citizens' Movement | Citizens' Movement | Citizens' Movement | Clemente Castañeda | Centre to centre-left |
| Solidarity Encounter Party | Solidarity Encounter Party | Solidarity Encounter Party | Hugo Eric Flores Cervantes | Right-wing |
| Progressive Social Networks | Progressive Social Networks | Progressive Social Networks | José Fernando Gonzalez Sánchez | Centre-left |
| Force for Mexico | Force for Mexico | Force for Mexico | Gerardo Islas Maldonado | Centre-left |

### Juntos Hacemos Historia

In June 2020, Alfonso Ramírez Cuéllar, president of the National Regeneration Movement (Morena), announced an alliance with the Labor Party (PT), and the Ecologist Green Party of Mexico (PVEM), expressing full support for Andrés Manuel López Obrador's legislative agenda.
On 23 December 2020, Mario Delgado, the new president of Morena, introduced the Juntos Hacemos Historia electoral alliance, a coalition comprising Morena, PT, and PVEM. Initially planned for the coalition to run together in 150 of the 300 electoral districts, the alliance was expanded on 18 March 2021, to cover 183 districts.
* Juntos Hacemos Historia
* Candidate from MORENA (88)  Candidate from PVEM (50)  Candidate from PT (45)  No coalition candidate

### Va por México

On 22 December 2020, the National Action Party (PAN), the Institutional Revolutionary Party (PRI) and the Party of the Democratic Revolution (PRD) formed the opposition electoral alliance Va por México. Initially planned to run together in 180 of the 300 electoral districts, on 23 December, the number was decreased to 171. On 15 February 2021, the alliance was expanded to cover a total of 219 districts.
Citizens' Movement (MC) announced that they would not form an alliance with the PAN and PRD, as they had in 2018, and would instead contest the election independently, citing disagreements with the parties.
* Va por México
* Candidate from PRI (77)  Candidate from PAN (72)  Candidate from PRD (70)  No coalition candidate

## Opinion polls

| Poll Source | Date Published | Date of Poll | Sample Size | Margin of Error | | | | | | Other | Undecided/No Answer |
| Massive Caller | August 2020 | No Data | 600 | No Data | 40% | 11.8% | 24.2% | 2.16% | 3.23% | 18.4% | No Data |
| GEA-ISA | 17 September 2020 | 5–7 September 2020 | No Data | No Data | 22% | 17% | 14% | - | - | 7% | 40% |
| Massive Caller | 19 October 2020 | No Data | 600 | ±4.3% | 41.8% | 12.3% | 31.7% | 2.3% | 3.4% | 8.5% | No Data |
| El Universal | 30 November 2020 | 12–17 November 2020 | 1000 | ±3.54% | 32% | 16% | 17% | 4% | 3% | No Data | No Data |
| Mitofsky | 17 December 2020 | No Data | No Data | No Data | 28.4% | 10.8% | 14.9% | 2.6% | 2.6% | 9.8% | 30.9% |
| Mitofsky | 27 December 2020 | No Data | No Data | No Data | 27.4% | 13.9% | 12.4% | 3.3% | 1.4% | 5.8% | 35.8% |
| El Financiero | 4 February 2021 | 15–16 and 29–30 January 2021 | 1000 | ±3.1% | 38% | 10% | 11% | 3% | - | No Data | 33% |
| Massive Caller | 22 February 2021 | 19 February 2021 | 600 | ±4.1% | 51.3% | 10.7% | 31.3% | 2.0% | 2.2% | No Data | No Data |
| El Financiero | 4 March 2021 | 12–13 and 25–26 February 2021 | 1000 | ±3.1% | 44% | 10% | 10% | 3% | - | No Data | 29% |
| El Financiero | 8 April 2021 | 2–13 and 26–27 March 2021 | 1000 | ±3.1% | 40% | 10% | 11% | 3% | - | No Data | 27% |
| Parametría | 10 April 2021 | 31 March – 10 April 2021 | 800 | ±3.5% | 32% | 11% | 12% | 3% | 4.5% | 12.5% | 25% |
| Massive Caller | 16 April 2021 | 1–15 April 2021 | 600 | ±4.3% | 42.1% | 17.8% | 24.1% | 3.4% | 4.8% | 7.8% | No Data |
| Reforma | 16 April 2021 | 8–13 April 2021 | 1200 | ±4.2% | 45% | 18% | 17% | 4% | 3% | 13% | No Data |
| El Financiero | 5 May 2021 | 29 April – 2 May 2021 | 2000 | ±3.1% | 40% | 20% | 19% | 3% | 5% | 13% | No Data |
| El País | 17 May 2021 | 10–14 May 2021 | 2000 | ±3.46% | 44% | 19% | 18% | 3% | 5% | 8% | — |
| GEA-ISA | May 2021 | 14–17 May 2021 | 1500 | ±2.5% | 29.7% | 13.0% | 15.6% | 4.6% | 5.8% | 9.8% | 21.5% |
| Varela y Asociados | 25 May 2021 | 29 April – 5 May 2021 | 1500 | No Data | 46% | 15% | 17% | 5% | 5% | 12% | — |
| El Universal | 27 May 2021 | 19–25 May 2021 | 1530 | ±2.86% | 41% | 15.3% | 15.9% | 3% | 7.9% | 16.9% | — |
| Parametria | 1 June 2021 | 22–28 May 2021 | 1000 | ±3.1% | 40% | 16% | 15% | 3% | 7% | 19% | — |
| El Financiero | 2 June 2021 | 14–15, 28–29, 27–30 May 2021 | 2000 | ±2.86% | 39% | 20% | 21% | 3% | 5% | 12% | — |
| Reforma | 2 June 2021 | 22–30 May 2021 | 2000 | ±2.8% | 43% | 20% | 18% | 2% | 7% | 10% | — |

## Conduct
### Possibility of post-election protests

Prior Mexican elections have been fraught with accusations of election fraud, this had led to massive protests after the majority of Mexican elections in the past two decades. The 2021 legislative election did not cause protests. In a speech on 14 June, President Andrés Manuel López Obrador said "We must celebrate it, because we achieved our purpose: to establish in Mexico an authentic, a true democracy."

### Political assassinations

The runup to the 2021 legislative election in Mexico was filled with political assassinations. More than 91 politicians were killed, 14 of them being candidates. This political violence led to the 2021 elections being labeled as the second most deadly election since the year 2000.

## Absentee voting

Mexican citizens from eleven states who live overseas can vote electronically or by mail. Most of the elections are for governor, but overseas citizens registered in Mexico City, Jalisco, and Guerrero will be able to vote in state legislative elections.
INE approved a pilot program allowing prison inmates who are held in protective custody in Hermosillo (District 4, Sonora); Villa Comaltitlán, Chiapas; Coatlán del Río (District 4 Jojutla, Morelos); and Buena Vista Tomatlán (District 12 Apatzingán, Michoacán) to vote absentee from 17–19 May 2021. The present order covers only male inmates, but it may be extended to females.

## Results

Approximately 49 million votes were cast in the election, with a turnout of 52.7%, a 5% increase in voter participation compared to the 2015 legislative election. This was the largest midterm election in Mexican history.
The ruling coalition, Juntos Hacemos Historia, retained a 27-seat majority in the Chamber of Deputies with about 44% of the vote, but lost a significant number of seats, resulting in the loss of the two-thirds supermajority it held during the LXIV Legislature. Va por México, securing 41% of the vote, won 199 seats, increasing their representation by 52 seats. Citizens' Movement earned 23 seats, a loss of 4 compared to the previous election. No newly established party secured any seats.
Many commentators saw the election as an electoral stalemate for President Andrés Manuel López Obrador, as the ruling coalition only achieved a majority and not his desired two-thirds supermajority. Some said López Obrador might negotiate to bring his policies to fruition. Others said he could attempt to flex his executive muscle and brute force changes by using his powers as president.
Seat distribution by coalition (left) and party (right) :
| Party or alliance | Party or alliance | Party or alliance | Party or alliance | Party-list | Party-list | Party-list | Constituency | Constituency | Constituency | Total seats | +/– |
| Party or alliance | Party or alliance | Party or alliance | Party or alliance | Votes | % | Seats | Votes | % | Seats | Total seats | +/– |
| | Juntos Hacemos Historia | | Morena | 16,756,189 | 35.30 | 76 | 16,629,905 | 35.27 | 122 | 198 | +7 |
| | Juntos Hacemos Historia | | Ecologist Green Party of Mexico | 2,670,677 | 5.63 | 12 | 2,659,178 | 5.64 | 31 | 43 | +27 |
| | Juntos Hacemos Historia | | Labor Party | 1,594,635 | 3.36 | 7 | 1,588,152 | 3.37 | 30 | 37 | –24 |
| | Juntos Hacemos Historia | Total | Total | 21,021,501 | 44.28 | 95 | 20,877,235 | 44.28 | 183 | 278 | +10 |
| | Va por México | | National Action Party | 8,967,785 | 18.89 | 41 | 8,896,470 | 18.87 | 73 | 114 | +33 |
| | Va por México | | Institutional Revolutionary Party | 8,715,191 | 18.36 | 40 | 8,663,257 | 18.37 | 30 | 70 | +25 |
| | Va por México | | Party of the Democratic Revolution | 1,792,348 | 3.78 | 8 | 1,785,351 | 3.79 | 7 | 15 | –6 |
| | Va por México | Total | Total | 19,475,324 | 41.03 | 89 | 19,345,078 | 41.03 | 110 | 199 | +52 |
| | Citizens' Movement | Citizens' Movement | Citizens' Movement | 3,449,804 | 7.27 | 16 | 3,425,006 | 7.26 | 7 | 23 | –4 |
| | Solidarity Encounter Party | Solidarity Encounter Party | Solidarity Encounter Party | 1,352,388 | 2.85 | 0 | 1,344,835 | 2.85 | 0 | 0 | –56 |
| | Force for Mexico | Force for Mexico | Force for Mexico | 1,216,780 | 2.56 | 0 | 1,210,384 | 2.57 | 0 | 0 | New |
| | Progressive Social Networks | Progressive Social Networks | Progressive Social Networks | 868,444 | 1.83 | 0 | 864,391 | 1.83 | 0 | 0 | New |
| | Independents | Independents | Independents | 44,311 | 0.09 | 0 | 44,292 | 0.09 | 0 | 0 | 0 |
| | Non-registered candidates | Non-registered candidates | Non-registered candidates | 41,925 | 0.09 | 0 | 41,558 | 0.09 | 0 | 0 | 0 |
| Total | Total | Total | Total | 47,470,477 | 100.00 | 200 | 47,152,779 | 100.00 | 300 | 500 | 0 |
| Valid votes | Valid votes | Valid votes | Valid votes | 47,470,477 | 96.60 | | 47,152,779 | 96.60 | | | |
| Invalid/blank votes | Invalid/blank votes | Invalid/blank votes | Invalid/blank votes | 1,673,046 | 3.40 | | 1,660,363 | 3.40 | | | |
| Total votes | Total votes | Total votes | Total votes | 49,143,523 | 100.00 | | 48,813,142 | 100.00 | | | |
| Source: DOF, INE ||||||||||||

## Aftermath
### Election night

At around midnight Mexico City time, the INE published its official quick count, declaring that Juntos Hacemos Historia retained a majority in the Chamber of Deputies.

### Party registrations

Based on the 2021 PREP results, all three newly established parties—the Solidarity Encounter Party (PES), Progressive Social Networks (RSP), and Force for Mexico (FXM)—failed to reach the 3% threshold required to maintain their registration as national political parties. This marked the second time the PES lost its registration, having previously done so in 2018 when it was known as the Social Encounter Party. On 17 June, auditors were appointed to oversee the liquidation process for the three parties. On 30 September, the INE officially declared their loss of registration.

### Lawsuits
#### Results changes

Due to the annulment of ballot boxes in certain districts, the results in some constituencies changed, with Juntos Hacemos Historia losing three seats and Va por México gaining three.
* Baja California Sur's 1st – Changed from María Mercedes Maciel Ortiz (Juntos Hacemos Historia) to Marco Antonio Almendáriz Puppo (Va por México).
* Mexico City's 3rd – Changed from Gabriela Jiménez Godoy (Juntos Hacemos Historia) to Wendy González Urrutia [es] (Va por México).
* Nuevo León's 3rd – Changed from José Luis García Duque (Juntos Hacemos Historia) to Wendy Maricela Cordero González (Va por México).