The Texas House’s fifth most senior member appears to be on his way out. State Rep. René Oliveira, a Brownsville Democrat first elected in 1981, trailed challenger Alex Dominguez by 14 points late Tuesday, local voting returns showed.

In March, Oliveira, 63, finished first in the Democratic primary and was less than 2 points from avoiding a runoff. But since then, his campaign has been dogged by problems, most significantly his arrest last month for allegedly driving while intoxicated, which quickly became a central issue in the runoff election.

Dominguez, 47, came in second in the three-candidate primary in House District 37, which includes Brownsville and a large swath of Cameron County. At the time, he finished 12 points behind Oliveira.

But on Tuesday, runoff results showed Dominguez up with 57 percent of the vote to Oliveira’s 43 percent.

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Oliveira, because of his seniority, held a powerful perch in the Texas House, especially by a Democrat’s standards. He is the chairman of the House Committee on Business and Industry and a member of the influential State Affairs Committee.

A second incumbent, albeit one with far less tenure, was also on track to lose his Texas House seat Tuesday. Freshman state Rep. Scott Cosper, R-Killeen, lagged behind challenger Brad Buckley, a veterinarian, by 18 points, despite having a huge fundraising advantage.

Cosper had the financial backing of moderate Republican groups, including the Associated Republicans of Texas. His loss was notable given the success of the moderate groups’ other preferred candidates, who faced ultra-conservative challengers throughout the state. Buckley, however, did not run to Cosper’s right.

When Cosper first won the seat two years ago, it came down to a recount, with Cosper finishing just 43 votes ahead of his challenger.

Elsewhere, in notable legislative races, Sheryl Cole led Chito Vela by 2 points in the bid to replace another ousted incumbent, state Rep. Dawnna Dukes, D-Austin. Cole, a former Austin City Council member, had outraised Vela, a criminal defense and immigration attorney, and collected several high-profile endorsements from local officials in Austin. If Cole wins, she will likely continue a 43-year legacy of the seat being represented by a black woman, the only African-American member of the Travis County delegation at the Capitol.

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