Tesla and SpaceX CEO Elon Musk has been revealed as a top donor to a Republican PAC aimed at keeping control of Congress. Filings published by ProPublica this weekend show Musk contributed $38,900 to the Protect the House PAC, joining the likes of casino magnate Sheldon Adelson and Houston Texans owner Robert McNair in the PAC’s top 50 donors. The PAC raised more than $8 million in the second quarter for Republican lawmakers hoping to fend off Democratic challengers. Musk, who called claims that he is a top donor to the GOP “categorically false,” has a history of donating to both parties. His contributions to the Republican Party raised eyebrows on Twitter, however, as many questioned how the “socially liberal” billionaire vowing to fight climate change could support the GOP’s platform.