HARLINGEN, Texas (Border Report) — Republicans have thrown millions of dollars into TV advertising and have launched an all-out effort to ensure that three South Texas congressional border districts — which have traditionally been Democratic — will vote red this Election Day.

Texas’ 15th Congressional District

The GOP wants to win Texas’ 15th Congressional District, a swath of land that extends from the border of northern Mexico in Hidalgo County, Texas, to outside San Antonio. Conservative Republican Monica De La Cruz is again vying for this district.

De La Cruz narrowly lost in 2020 and is hoping this time to defeat her Democratic opponent, Michelle Vallejo, who has led a low-funded grassroots campaign that didn’t get off the ground until June when she won a recount for her party.

Texas’ 28th Congressional District

Republicans also have their eyes on Texas’ 28th Congressional District and want to unseat longtime Democratic incumbent U.S. Rep. Henry Cuellar, of Laredo, who is vying for his 10th term in Congress.

His opponent is political newcomer Cassy Garcia, the wife of a U.S. Border Patrol agent. She has never held office but used to work for U.S. Sen. Ted Cruz, R-Texas.

Texas 34th Congressional District

And Republicans want to ensure that current U.S. Rep. Mayra Flores holds her seat and returns in 2023 to represent Texas’ 34th Congressional District, which includes the Gulf Coast and the border port city of Brownsville.

Flores won this seat in a special election in June. But she faces Democratic U.S. Rep. Vicente Gonzalez, who is fighting to stay in Congress after having to switch districts from the 15th to the 34th. The Republican-led Texas Legislature in 2021 redrew the boundaries of both districts and Gonzalez’s McAllen home is now in the 34th District.

The 15th District is of particular importance to Republicans who want to claim the open seat. But Democrats don’t want to give it up and on Monday pulled out the stops by inviting former President Bill Clinton to rally the vote for Vallejo.

Republican Monica De La Cruz (left) and Michelle Vallejo (right) will face-off in a competitive midterm race that could affect the balance of power in Congress.

Clinton spoke before 600 people in Edinburg, Texas, on Monday afternoon, after holding a get-out-the-vote rally that morning in Laredo for Cuellar, who once served as a campaign manager for him.

538 poll on Monday had De La Cruz and Vallejo in a virtual dead heat.

But De La Cruz has out-fundraised Vallejo by two-to-one and she has been campaigning almost non-stop since losing in 2020 and is a well-known entity in the district. In counties north of the border, which tend to favor Republicans, she has signs that read “THIS IS MONICA COUNTRY.”

The 15th District now also favors Republicans, after the Texas Legislature changed its boundaries.

Political analysts say in order to hold this district Democrats will have to get out and vote.

Early voting leading up to Tuesday’s elections shows lackluster participation with less than 25% of voters in Hidalgo County casting ballots by Nov. 4, according to the Texas Secretary of State.

“Candidate Monica De La Cruz is the frontrunner for the Republicans to do what hasn’t been done in quite some time and that is to have a district in the Valley represented by a Republican,” Natasha Altema McNeely, associate professor of political science for the University of Texas Rio Grande Valley, told Border Report.

Although polls show De La Cruz and Vallejo locked in a tight race, many recognize that Vallejo has far less campaigning experience. And the Democratic Congressional Campaign Committee refused to finance TV advertising for Vallejo, although they did supply office staff and resources, the organization told Border Report.

Republicans are hoping to take advantage and seize momentum that De La Cruz has been pushing in relentless campaigning.

They also feel they have momentum in District 34 with a GOP sitting member in Congress currently representing it.

U.S. Reps. Mayra Flores, R-Texas, and Vicente Gonzalez, D-Texas, are fighting for Texas’ 34th Congressional District. (Photo of Flores by Border Report; Photo of Gonzalez by Gonzalez staff.)

“Primarily the two districts, 15 and 34, in which Republicans since 2020 have had their eyes on. These coveted districts that have a majority Hispanic population the Republicans would really like to win those and to show that ‘look this racial and ethnic minority group, which has historically been affiliated and supported the Democratic Party, is actually moving its alliance to the right,” McNeely said.

Cuellar, in District 28, is a moderate Democrat who has voted with Republicans, like in 2021 against codifying abortion rights. He is vice chairman of the House Appropriations Homeland Security Subcommittee, and in line to chair the subcommittee in 2023 if Democrats hold control of the House.

U.S. Rep. Henry Cuellar, D-Texas, right, is opposed by Republican political newcomer Cassy Garcia for Texas’ 28th Congressional District.

The 538 poll has Cuellar favored to beat Garcia by a large margin.

If voters are leaning conservative on the South Texas border then McNeely says Cuellar’s voting record should help his cause.

“Although he uses the label ‘moderate,’ he’s actually quite conservative by some of his legislative behavior,” she said.

Polls close at 7 p.m. CST.

Border Report will update with election results throughout the evening.

Sandra Sanchez can be reached at Ssanchez@borderreport.com