U.S. Sen. Elizabeth Warren is unveiling her first major round of endorsements ahead of a Texas primary that is becoming increasingly contested by some top-tier Democratic presidential candidates.

In an announcement first shared with The Texas Tribune, Warren’s campaign unveiled an endorsement list that now includes three state representatives, several Texas city council members and political organizers.

The three San Antonio City Council members on the list were part of the first wave of Texans who last year supported Julián Castro, the former U.S. housing secretary and San Antonio mayor who dropped his White House bid earlier this month and quickly endorsed Warren as the Democratic nominee.

Warren has been the most proactive candidate in building a formal organization here, but fellow candidate Joe Biden has been leading the way in endorsements. The former vice president unveiled his own list of new endorsers earlier this week — a lineup that included eight people who had previously been with Castro.

Warren’s endorsers now include state Rep. Sheryl Cole, D-Austin. She joins state Reps. Erin Zwiener, D-Driftwood, and Shawn Thierry, D-Houston, who had already announced their support.

The list also includes Austin City Council members Natasha Harper-Madison, Ann Kitchen, Leslie Pool, Paige Ellis and Kathie Tovo. Warren also earned the endorsement of San Antonio City Council members Roberto Treviño, Shirley Gonzales and Manny Pelaez. Several Austin and San Antonio civic and political leaders have also signed on.

“I’m honored to have earned the support of such dedicated leaders, who have fought to make Texas a better place for working families and led the charge on issues like small business development, education, Black maternal health, resource and pay equity, health care, and affordable housing,” Warren said in a statement. “Together, we’ll build a movement to make our country and our economy work for everyone.”

The new endorsements come on the heels of the Massachusetts senator opening field offices in San Antonio and Austin last month. Warren is also one of three candidates — including Biden and billionaire Michael Bloomberg — to hire a Texas state director.

Still, Warren has plenty of work to do to improve her standing in Texas. She’s been overshadowed in the race for Texas endorsements by Biden and came in second to him in the latest University of Texas/Texas Tribune poll.

But she’s found a potentially powerful Texas ally in Castro, who appeared with her at an event in Brooklyn earlier this week and plans to campaign with Warren through the weekend. Castro will stump for Warren in Nevada on Friday and Saturday before joining her for a town hall in Iowa on Sunday.

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