Elon Musk is now a Republican mega-donor.

Musk, estimated to be the world's richest person, was the sole donor to the political action committee he created, America PAC, a group that spent about $72 million to support Donald Trump's reelection bid between July and September, according to a new quarterly filing with the Federal Election Commission.

Musk's $75 million in giving was among several big fundraising hauls disclosed Tuesday in filings with the FEC. The filings show Musk joined other prominent Silicon Valley figures in supporting Trump, including the venture capitalists Marc Andreessen and Ben Horowitz, who each donated $2.5 million to a super PAC aligned with the former president. (Horowitz has since said that he will make a "significant donation" to support Harris.)

Since its launch in May, Musk's super PAC has quickly emerged as a key piece of the effort to return Trump to the White House, working to turn out the vote in key swing states. Musk endorsed Trump in July following the failed assassination attempt against the former president, and has gone on to become a vocal supporter. Earlier this month, the billionaire head of Tesla and SpaceX even appeared on stage with Trump when he returned to the site of the assassination attempt.

Outside of Silicon Valley, Miriam Adelson, a long-time power-player in Republican politics alongside her late husband, casino magnate Sheldon Adelson, has funded her Preserve America super PAC to the tune of $100 million so far this year.

Railroad heir Timothy Mellon is this cycle's largest individual donor. He contributed $125 million to the Make America Great Again super PAC earlier this year.

Despite the glut of money in the outside Republican groups, the groups most closely connected to Trump's campaign have failed to match Vice President Harris' fundraising numbers. Trump 47, which faces fewer rules than super PACs and shoulders a great deal of his campaign expenses, raised $145 million this summer.

Vice President Harris' comparable joint fundraising group, the Harris Victory Fund, raised $633 million during the same time period.

Her allied super PAC, known as Future Forward, has raised $175 million this calendar year, which includes time when President Biden was on the ticket.

The group's largest individual supporters are Mike Bloomberg, who has contributed $19 million, and LinkedIn founder Reid Hoffman, who gave $10 million.