The Texas Senate’s most conservative Democrat may not be invincible.

In Brownsville, a Goliath has stumbled. After 29 years in the Texas Senate, Eddie Lucio—the upper chamber’s most conservative Democrat—has been pushed into a runoff. Facing two opponents in his first serious challenge since 1992, the 74-year-old Lucio fell just a fifth of a percentage point shy of winning State Senate District 27’s Democratic primary outright. Lucio will now face Sara Stapleton-Barrera, a Brownsville trial attorney and daughter of a former Cameron County Democratic chair who’s never held public office.

Over the years, Lucio’s made plenty of enemies. Early on, he pushed pro-business “tort reform,” alienating unions and farmworkers. Both pious and prejudiced, he has consistently voted against LGBTQ rights and women’s reproductive freedom. In recent weeks, a host of progressive groups either endorsed one of his challengers or simply endorsed against him. If Stapleton-Barrera—who supports LGBTQ rights and is comparatively liberal on abortion—can ultimately unseat him, that should add a senator to the Democratic column in some votes.

But Lucio has powerful friends with deep pockets, including the anti-consumer Texans for Lawsuit Reform and groups tied to the Koch brothers.

In a phone interview last year, Lucio told me he wants to serve at least one more term so he can influence the legislative redistricting process. Lucio—who still opposes same-sex marriage—also said he’d be sticking to his old ways. “Maybe there’s a new wave I’m not aware of,” he conceded, but “my faith leads me to my decision making. … I won’t change that because of modern trends.”

Stapleton-Barrera’s success is its own surprise: With 36 percent of the vote, she trounced the third candidate in the race, Ruben Cortez, a sitting State Board of Education member. According to Texas Ethics Commission filings, the 36-year-old Stapleton-Barrera ran a campaign primarily financed by loans from her husband, another Brownsville attorney, and was handily outspent by Lucio, who dropped over $1 million since July. But University of Texas Rio Grande Valley political scientist Sylvia Gonzalez-Gorman, told me in September that Stapleton-Barrera had a path to victory: “She’s really banking on this generational, gender shift we saw play out in the 2018 midterms.”

The race now has shades of a 2018 upset: Longtime Brownsville state Representative René Oliveira, in a three-way race, was narrowly pushed into a runoff with one-term Cameron County Commissioner Alex Dominguez. Dominguez then won the second contest. (Oliveira did not help his cause by getting charged with a DWI in the interim.)

The runoff is set for May 26, and whoever emerges will have effectively won the deeply blue district. On Wednesday morning, I texted Stapleton-Barrera to ask how she felt about her upset. “I feel excited and ready to rumble!” she replied.

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