U.S. Sen Bernie Sanders of Vermont has endorsed Tallahassee Mayor Andrew Gillum for Florida governor, providing a progressive boost to the candidate in the hotly contested race.

Sanders, who is known for being stingy with his endorsements, having refused to back his own son, took to Twitter on Wednesday, saying he was “proud” to back Gillum, only non-millionaire in the race, for the Democratic nomination. 

“As governor, Andrew Gillum will work to provide health care for all through a Medicare-for-All program, raise the minimum wage to a living wage, invest in sustainable energy, improve education, make sure the wealthiest corporations pay their fair share of taxes and be welcoming to immigrants,” said Sanders. “Andrew has never backed down from a fight, including beating the NRA and standing up against xenophobic politicians. Andrew Gillum will set a new course for Florida — a governor who represents all the people and not just powerful special interests.”

On Wednesday, Gillum, said it was “an honor” to have Sanders’ support.

“He has been an unapologetic fighter for working people and progressive values across the country,” Gillum said on Twitter. 

The mayor has thus far trailed his opponents in polling and fundraising. Recent polls show former Congresswoman Gwen Graham, who is reportedly sitting on a $10.4 million war chest, leading the race with 20 percent support. 

Gillum and Graham face three other opponents in the Aug. 28 primary—billionaire developer Jeff Greene, Winter Park millionaire businessman Chris King and former Miami Beach Mayor Philip Levine, who has declared his net worth at $133 million and poured millions into his campaign, helping to raise more than $20 million between his campaign and political committee. 

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