AUSTIN — Jessica Cisneros, a 26-year-old immigration attorney from Laredo, raised more money in the first six weeks of the year than the longtime Democratic congressman she’s challenging, with the help of a few famous supporters, including actress Susan Sarandon.

U.S. Rep. Henry Cuellar, the House District 28 incumbent backed by both the Democratic establishment and the Koch Brothers, still has far more money on hand — more than $2 million — just days before the March 3 primary. But Cisneros, who raked in more than $350,000 over the first six weeks of the year, outraised Cuellar by $100,000. She ended the period with just less than $296,000.

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Among Cisneros' donors were Sarandon, who gave $2,000, and model Cameron Russell, who chipped in $500. Tommy Vietor, a former spokesman for Barack Obama who now hosts the popular podcast Pod Save America, gave $1,000.

Ezra Koenig — the lead singer of Vampire Weekend, whose band has performed at Bernie Sanders rallies — gave $250 the day after Sanders endorsed Cisneros.

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Cuellar’s campaign has criticized the amount of money Cisneros has raised from outside Texas. She’s supported by Justice Democrats, a progressive group that backed U.S. Rep. Alexandria Ocasio-Cortez’s insurgent 2018 bid, as well as EMILY’s List, a group supporting progressive women candidates.

Colin Strother, a campaign spokesman, has accused Cisneros of being “bought and paid for” by national groups.

“This is Cuellar Country and this seat is not for sale," he said last month.

ben.wermund@chron.com