Two groups backed by former New York mayor Michael Bloomberg have spent a combined $11 million on digital ads this election cycle, the largest digital investment ever made by a Democratic nonprofit.

The two groups — Everytown for Gun Safety and Independence USA PAC — have poured money into key House races across the country, outspending even the GOP House Majority PAC, Axios reported Thursday.

Bloomberg, a former Republican and political independent, has emerged as a prominent Democratic activist and donor since President Trump took office. The 79-year-old billionaire formally changed his party affiliation to Democrat earlier this month, in the latest early sign that he may run for president himself.

“Today, I have re-registered as a Democrat — I had been a member for most of my life — because we need Democrats to provide the checks and balances our nation so badly needs,” he said.

Bloomberg has to date spent a total $80 million to help Democrats retake the House and his advisers told the Washington Post earlier this month that he planned to spend an additional $20 million on key Senate races via Independence USA PAC.

While the billionaire activist received a warm welcome as the keynote speaker at the Pennsylvania Democratic party’s fall dinner on Sunday, his Republican defection has not been well received by the party’s progressive wing.

“I can’t think of anyone more misaligned with where the Democratic party is right now,” Representative Ro Khanna (D-Calif.) told the Washington Post. “The party is not going to nominate someone who spoke at George W. Bush’s convention.”

Despite his support for stop-and-frisk policing and his past spending on behalf of Republicans, Bloomberg appears optimistic about his efforts to turn the Democratic party toward the political center.

“No one ever thought Trump could win, either,” Bloomberg told the Post. “Nobody thought I could win.”