LXVI Legislature of the Mexican Congress

66th Congress
*(LXVI Legislatura)*
66th Congress; (LXVI Legislatura)
	Legislative Palace of San Lázaro
Overview
Legislative body	Congress of the Union
Term	1 September 2024 – 31 August 2027
Election	2 June 2024
Senate
Members	128 senators
President	Gerardo Fernández Noroña; (1 September 2024 – present);
Chamber of Deputies
Members	500 deputies
President	Ifigenia Martínez y Hernández; (1 September – 5 October 2024); Sergio Gutiérrez Luna; (8 October 2024 – present);

The LXVI Legislature of the Congress of the Union (66th Congress) is the current session of the legislative branch of Mexico, composed of the Chamber of Deputies and the Senate of the Republic. It convened on 1 September 2024, and will end on 31 August 2027,^[1] covering the final month of Andrés Manuel López Obrador's term in office and the first three years of Claudia Sheinbaum's presidency.

Both chambers of Congress were elected in the 2024 general election. There were three competing forces: the Sigamos Haciendo Historia coalition, consisting of the National Regeneration Movement (Morena), the Labor Party (PT), and the Ecologist Green Party of Mexico (PVEM); the Fuerza y Corazón por México coalition, comprising the National Action Party (PAN), the Institutional Revolutionary Party (PRI), and the Party of the Democratic Revolution (PRD); and the Citizens' Movement (MC), the only party to run without allies.

Sigamos Haciendo Historia won a supermajority in the Chamber of Deputies, granting the ruling coalition 73% of the seats, the highest share since the LII Legislature in 1982, during Miguel de la Madrid's presidency.^[2] Although the coalition fell three seats short of a supermajority in the Senate, defections by two senators elected for the PRD on 28 August closed the gap to one.^[3] The supermajority was ultimately secured with the defection to Morena of Cynthia López, elected for the PRI in Mexico City, on 12 November.^[4] This marked the first time since the LIII Legislature in 1985 that the ruling coalition held a supermajority in both chambers.^[5]

^ "No habrá doble Congreso en agosto de 2024; se corrigió el error que pondría en jaque al Legislativo". Cámara de Diputados. 7 September 2023.
^ Staff, Forbes (2024-08-23). "INE da a Sheinbaum el mayor poder en Diputados desde 1982". Forbes México (in Spanish). Retrieved 2025-01-26.
^ "Mexico's ruling party edges closer to a majority in both houses of Congress after 2 senators defect". Associated Press. 28 August 2024. Retrieved 28 August 2024.
^ "Morena logra "supermayoría" en el Senado con la adhesión de Cynthia López Castro". Brújula Política. 12 November 2024. Retrieved 5 January 2025.
^ Del Carmen Nava Polina, María; Weldon, Jeffrey; Yáñez López, Jorge. "Cambio político, presidencialismo y producción legislativa en la Cámara de Diputados: 1988-1998" (PDF). Retrieved 2025-01-25.

[:3-1] "No habrá doble Congreso en agosto de 2024; se corrigió el error que pondría en jaque al Legislativo". Cámara de Diputados. 7 September 2023.

[2] Staff, Forbes (2024-08-23). "INE da a Sheinbaum el mayor poder en Diputados desde 1982". Forbes México (in Spanish). Retrieved 2025-01-26.

[edgescloser-3] "Mexico's ruling party edges closer to a majority in both houses of Congress after 2 senators defect". Associated Press. 28 August 2024. Retrieved 28 August 2024.

[brujula-lopez-4] "Morena logra "supermayoría" en el Senado con la adhesión de Cynthia López Castro". Brújula Política. 12 November 2024. Retrieved 5 January 2025.

[5] Del Carmen Nava Polina, María; Weldon, Jeffrey; Yáñez López, Jorge. "Cambio político, presidencialismo y producción legislativa en la Cámara de Diputados: 1988-1998" (PDF). Retrieved 2025-01-25.

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