Andrew Gillum is getting some major last minute help from a couple familiar names.

Billionaire donors George Soros and Tom Steyer are directing $650,000 to Gillum's political committee, Forward Florida — a last-minute cash infusion aimed at boosting the Tallahassee mayor in the closing days of the Democratic primary of the Florida governor's race.

The donations, according to Politico which first reported them, come in the form of $250,000 from Soros, $300,00o from Steyer and another $100,000 from anonymous donors "affiliated with" the two billionaires.

"The surge is happening," Gillum campaign spokesman Geoff Burgan said in response to the donations. "The Gillum campaign is going to make history on Tuesday."

Steyer and Soros and their associated groups have already poured millions into Gillum's campaign since it launched in March of 2017. Most recently, Steyer's NextGen America gave $500,000 to Forward Florida between July 30 and August 14. Soros also gave Gillum's committee $250,000 last month.

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The contributions from Steyer and Soros have been a major boon to Gillum, the only non-millionaire running in the Democratic primary.

Olivia Bercow, a spokeswoman for NextGen America, said in a statement that Steyer's donation to Gillum reflects her group's excitement for his candidacy.

"We are seeing real momentum on the ground and in the polls for Andrew Gillum, and we're excited to help push Gillum, the most progressive candidate in the race, across the finish line on Tuesday," Bercow said.