Incumbent Texas Democrat Rep. Henry Cuellar, challenged in one of the most watched and most expensive primary contests in the country, emerged victorious, beating back a left-wing challenge from Jessica Cisneros. The race was close; Cuellar ended up with just 51.8 percent of the vote to Cisneros’s 48.2 percent.

The Laredo lawmaker is one of the most conservative Democratic House members in the country, a record that attracted a spirited challenge from Cisneros, a 26-year-old attorney who waged an insurgent campaign that presented a sharp contrast with Cuellar. Cisneros touted support for Medicare for All, the Green New Deal, and opposition to draconian immigration enforcement measures.

Despite representing a relatively safe Democratic seat in south Texas, Cuellar votes consistently with the Republican Party. He sided with the GOP in some 75 percent of his recent votes, including on measures against expanding worker access to labor unions and in support of repealing restrictions on predatory lending. Cuellar previously served in the cabinet of Republican Gov. Rick Perry and has been outspoken in his defense of President Donald Trump on contentious issues, including the president’s decision to assassinate Iranian Maj. Gen. Qassim Suleimani.

Many in the press compared the race to the 2018 bid by Alexandria Ocasio-Cortez 2018 to unseat Rep. Joe Crowley, D-N.Y., the third-ranking House Democrat and one of the most business-friendly Democrats in leadership. Cisneros also had the endorsement of Ocasio-Cortez, as well as the backing of Justice Democrats.

U.S. Rep. Henry Cuellar, D-Laredo, during a press conference to announce latest updates on the $30 million for humanitarian reimbursements to local governments and non-governmental organizations (NGOs) at the southern border at the Humanitarian Respite Center on Friday, July 19,2019 in McAllen. (Delcia Lopez/The Monitor via AP)

U.S. Rep. Henry Cuellar during a press conference at the Humanitarian Respite Center in McAllen, Texas, on July 19, 2019.

Photo: Delcia Lopez/The Monitor via AP

But there were important differences. Crowley, in many ways, was caught flatfooted and did not spend significant amounts of money until late in the New York primary. Cuellar prepared for this election for months, with allies flooding the district with attack ads accusing Cisneros of being as an outsider unfamiliar with the concerns of Texans and in favor of abortions. Cuellar’s campaign raised $1.7 million, almost half of which came from corporate political action committees.

Dark money flooded the district, with undisclosed cash from the American Bankers Association, the U.S. Chamber of Commerce, and a new group called American Workers for Progress, used to boost Cuellar over the last month. Cuellar is a favorite among the business lobbying community. Emails obtained by The Intercept show the lawmaker routinely providing favors for a border security company seeking contracts with the government after providing Cuellar with campaign contributions.

That’s not to say Cisneros did not also receive significant support. In the last fundraising period before the election, she out-raised Cuellar largely from small donors and through publicity she received via endorsements from Bernie Sanders, Elizabeth Warren, Ocasio-Cortez, and EMILY’s List. In the final days of the campaign, Working Families Party, the Texas AFL-CIO, and the SEIU helped Cisneros counter Cuellar’s advertising.

But the race provided a vivid display of the power of entrenched political interests from across the political aisle. Americans for Prosperity Action, the Super PAC founded and funded by right-wing billionaire Charles Koch, intervened in the race to support Cuellar, the very first time the group has supported a Democrat. House Speaker Nancy Pelosi and the Congressional Hispanic Caucus both worked to raise money for Cuellar over the last month.