Mexico's Chamber of Deputies rejected President Claudia Sheinbaum's proposed electoral reform on ‌March 11, La Jornada reported the same day. The rejection marks the Sheinbaum administration's first defeat in Congress since taking office in October 2024.

Parties allied with the government refused to back the bill, claiming it would allow the ruling National Regeneration Movement to concentrate power. The proposal obtained 259 votes in favor to 234 against, short of the 334 required to change the constitution. The bill aimed to reduce the number of senators by 25% to 96 and replace the election of plurinominal deputies (in which candidates are appointed to political lists by party leaders and assigned to Congress based on each party's total vote share) with a direct-vote system. Its goals also included reducing parties' and electoral bodies' public funding.