The chief financier of a leading pro-Roy Moore super PAC is a deep-pocketed Republican businessman who dropped eight figures on 2016 races alone and is looking to continue propping up the party’s most conservative candidates.

Illinois businessman Richard Uihlein provided $100,000 to the group, Proven Conservatives PAC, since September, according to a new filing with the Federal Election Commission, making him by far the group’s top donor. That money, which hadn’t been previously disclosed, has financed a host of ads boosting Moore’s candidacy in the face of widespread sexual assault and harassment allegations. The group has also run ads attacking Moore’s primary opponent, Sen. Luther Strange (R-AL), and his Democratic general election rival Doug Jones.

Proven Conservative PAC officially formed in late August, as the Alabama Senate primary contest heated up. The only major financial support it had previously reported came from a company owned by the family of Alabama timber executive Guice Slawson.

In addition to Uihlein, Proven Conservative received money in September from Peter Nicholas, a Florida-based businessman whose chain of Taco Bell franchises has also donated to the campaign of Omar Navarro, a quixotic Republican challenger to California Democrat Rep. Maxine Waters.

Uihlein is a far bigger name in GOP politics. The shipping and office supply mogul and his wife donated a combined $26.4 million to federal campaigns, party organs, super PACs, and interest groups during the 2016 election cycle, according to FEC data.

That spending has kept up this year. Uihlein is single-handedly bankrolling a pair of super PACs supporting the Wisconsin Senate campaign of businessman and Marine veteran Kevin Nicholson. That spending has led Democrats in the state to accuse Uihlein of trying to buy the Senate seat for his preferred candidate.

Nicholson, like Moore, received early backing from a coalition of populist-nationalist conservatives backed by Steve Bannon, Trump’s former chief strategist and the chairman of the right-wing website Breitbart News.

In late October, Breitbart lent space to Proven Conservative PAC’s chairman, Alabama Republican activist John Giles, to laud Moore’s qualifications. His column ran five days after Moore defeated Strange in the primary, and a week before the Washington Post first reported allegations that Moore had sexually assaulted a 14 year old and hit on other underage girls.

“President Donald Trump will love Senator Roy Moore,” Giles declared. In a previous endorsement of Moore, Giles, the former president of the Christian Coalition of Alabama, called the senate candidate “Jeff Sessions on steroids.”

With funds provided by Uihlein and a handful of other donors, Proven Conservative PAC has spent more than $120,000 on about 15 television spots for ads boosting Moore and casting Strange as a D.C. insider and Jones as a liberal extremist. While Uihlein has been active elsewhere, the PAC itself has not reported any electoral activity outside of Alabama.

A request for comment from Uihlein was not immediately returned.