Mexico’s ruling Morena party and its allies lost their supermajority in the lower congressional house in Sunday’s midterm elections, placing a check of sorts on President Andrés Manuel López Obrador’s nationalist energy agenda.


Preliminary results showed that the president’s coalition still holds simple majorities in the senate and the chamber of deputies, which is enough to pass legislation.

Amending the constitution, however, requires approval of two-thirds majorities in each chamber, along with simple majorities in at least half of the state legislatures.

Proponents of Mexico’s market-opening 2013 energy reform had expressed concern about López Obrador, aka AMLO, seeking to amend the constitution in order to give Mexico’s state-owned energy firms a leg up over their private sector counterparts.

The most controversial changes championed by the president include reforms to the electricity and hydrocarbon laws that were approved by legislators, then halted by the courts amid a barrage of lawsuits on antitrust and environmental grounds. 

The inability of Morena and its allies to secure a supermajority “does call…into question the political capital and leverage that AMLO has in procedural terms,” Verisk Maplecroft’s Karla Schiaffino, Americas senior analyst, told NGI’s Mexico GPI. “What I think is that moving forward, it will be increasingly difficult for him to enact the changes that he set himself up to do.”

The result was by no means a total loss for Morena, Schiaffino said, noting that holding simple majorities in each house “has actually served them well in making important changes.”

She added, “Another important point to consider is whether the opposition will coordinate as they did electorally” when it comes to legislating. “We did not see this during the first half of AMLO’s administration, however, the opposition has seen that…coordination does pay off.”

Sunday’s election was Mexico’s largest ever in terms of the number of seats up for grabs. These included all 500 seats in the chamber of deputies, along with 15 governorships and thousands of state legislative posts and local-level positions. 

Preliminary results compiled by national electoral institute INE showed that Morena had captured between 190 and 203 seats in the lower house, aka the chamber of deputies.

In second place was the opposition Partido Acción Nacional (PAN) with 106-117 seats, followed by the Partido Revolucionario Institucional (PRI) with 63-75 seats.

[View Pricing Now: NGI’s Mexico Gas Price Index calculates natural gas pricing on the border and within Mexico daily.]

Morena-allied parties the Partido Verde Ecologista de México, Partido del Trabajo, and Partido Encuentro Solidario won up to 48, 41, and six seats respectively, INE said. 

In other words, Morena and its allies will have a simple majority of at most 298 when the new legislative session begins on Sept. 1, down from 338 seats currently. The next senatorial and presidential elections are scheduled for 2024.

Preliminary results also indicated that Morena and its allies won at least 10 of the 15 governorships up for grabs.

Dozens of candidates were killed during the campaign season, a grim reminder of the intractable violence and narco-terrorism that no Mexican president in recent history has managed to quell.

Election day itself was relatively peaceful and orderly by most accounts. “There have been few elections like the ones yesterday, and I say this because the elections yesterday were free, clean, which did not happen in other times,” López Obrador said in his daily press briefing on Monday.

Business chamber Consejo Coordinador Empresarial, which has often been at odds with the current government, praised election officials and Mexican citizens for participating “with responsibility and civility” in the electoral process, and pledged to seek collaboration with the government going forward.