Billionaire environmentalist Tom Steyer is jumping into the crowded Florida gubernatorial race with a major financial investment that could alter the course of the Democratic primary.

On Friday, Steyer’s organization, NextGen America, will formally endorse Democratic candidate and Tallahassee mayor Andrew Gillum. In turn, the group and its founder will make an investment of more than $1 million towards Gillum’s campaign. The money represents the largest financial commitment that Steyer has made to a single candidate in a primary. And it will almost assuredly alter one of the premiere gubernatorial contests in the nation.

“As we battle for the heart and soul of this nation, Andrew Gillum is the kind of leader we need on the front lines,” Steyer said in a statement. “He’s someone we can trust to do the right thing, to put the people before the powerful, and who is unafraid to stand up for justice, now when we need it most.”

As part of his investment, Steyer will be personally sending a $500,000 grant to Forward Florida, the political committee affiliated with the Gillum campaign. The remainder of the money will be spent on boosting Gillum vis-a-vis a variety of existing NextGen functions, including on-the-ground organizing, field programs and digital and mail campaigns to turn out voters under 40.

The first digital ad that NextGen produced on Gillum’s behalf triumphantly declares that he “represents Florida’s future.”

An aide said that the money spent could grow as the campaign progresses. But even the initial investment from Steyer could prove critical in helping Gillum emerge from a crowded primary field. The Tallahassee mayor, who has had only modest fundraising success to date, faces six primary challengers in the race to replace Governor Rick Scott, who is now running for incumbent Sen. Bill Nelson’s (D-FL) seat. In some early polling, he has trailed former Rep. Gwen Graham (D-FL) and Miami Beach mayor Philip Levine who is pumping a lot of his own money into the race.

NextGen America says it has already registered over 13,000 young Floridian voters and received 15,000 pledged voters.