Republicans strengthen hold on Texas-Mexico border, retain key US house seat

Austin, Texas: Republican Representative Monica De La Cruz won her reelection bid on Tuesday, strengthening the GOP’s presence along the U.S.-Mexico border. De La Cruz, who represents a predominantly Latino and working-class district stretching from San Antonio to the Rio Grande Valley, centred her campaign on border security, an issue that resonated with her voters. She is on track to win by a larger margin than in 2022, where she faced Democratic challenger Michelle Vallejo in a rematch.

Shifting political landscape in South Texas

De La Cruz’s victory marks another sign of growing Republican strength in South Texas, a region that has traditionally been a Democratic stronghold. The GOP has invested heavily in the area, particularly since former President Donald Trump's success in 2020, when several counties in the region shifted toward the Republicans. This trend continued in 2024, with Trump flipping Cameron County, one of the largest counties along the Texas-Mexico border.

Tight races in other border districts

While De La Cruz’s race was settled, other Texas-Mexico border contests remain too close to call. Democratic Representatives Henry Cuellar and Vicente Gonzalez faced tough challenges in their respective districts. Cuellar, who has represented the 28th Congressional District since 2005, was running against Republican Jay Furman, a Navy veteran and political newcomer. This election is the first since Cuellar and his wife were implicated in bribery charges related to an Azerbaijani energy company and a Mexican bank. However, Cuellar’s race has garnered less attention than in 2022, when a multimillion-dollar GOP effort still failed to unseat him.

De La Cruz makes history in South Texas

De La Cruz made history in 2022 as the first Republican to win a congressional race in South Texas, a region that has been deeply Democratic for decades. Her victory was aided by the creation of the 15th Congressional District following the 2020 census, which was drawn by Republican mapmakers to favour their party. The district’s large Hispanic population, however, is a key demographic that both parties are keen to appeal to.

In her campaign, Vallejo focused on protecting programs like Social Security and Medicare, which are particularly important to her Latino and working-class base. De La Cruz, on the other hand, emphasised border security policies, including those supported by former President Trump, a central issue for many voters in the district.

Republicans set sights on Gonzalez and Flores race

In another closely watched race, Republican Mayra Flores was challenging Democratic Rep. Vicente Gonzalez in a rematch. Flores, who previously held the seat after a special election in 2022, has become a rising star within the GOP, especially in the border region. Republican House Speaker Mike Johnson campaigned for Flores, and she has outraised Gonzalez in what is expected to be one of the GOP's key battlegrounds.

The Texas-Mexico border region has seen significant shifts in political dynamics since 2020, with increasing Republican support in traditionally blue counties. Border security has emerged as a top concern for voters in the area, driving the region's rightward shift.

The changes in political alignment have led to a surge in Republican investment in these once-Democratic districts. In places like Hidalgo County, a historically Democratic stronghold, Biden’s margin of victory in 2020 was significantly smaller than in 2016, signalling a realignment in voter preferences. In rural areas like Zapata County, Trump flipped the county that had been solidly Democratic in 2016.

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