Political leanings: Conservative/Republican2024 total spending: $296.6 millionThe Senate Leadership Fund, or SLF PAC, is a Republican super PAC that was established in 2015 by allies of Sen. Mitch McConnell, who was Senate majority leader at the time. It is “solely dedicated” to “protecting and expanding the Republican Senate Majority.” As a super PAC, SLF PAC can accept unlimited contributions, but it must disclose its donors and cannot coordinate its spending with candidate campaigns. As of June 30, the Senate Leadership Fund had raised a total of $253.7 million for the 2026 midterms, according to its most recent quarterly financial report to the Federal Election Commission. One Nation is led by Steven Law, who headed the Senate Leadership Fund until he stepped down in 2024.