
Political leanings: Conservative/Republican
2024 total spending: $296.6 million
The 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.
The group, now connected to Republican Senate Majority Leader John Thune, says its mission is to “support strong Republican candidates in competitive states, leveraging best-in-class campaign tactics and standards to aggressively counter the Democratic machine.” It is “solely dedicated” to “protecting and expanding the Republican Senate Majority.” Its executive director is Alex Latcham, a former deputy assistant to President Donald Trump and former director of the White House Office of Public Liaison.
As a super PAC, SLF PAC can accept unlimited contributions, but it must disclose its donors and cannot coordinate its spending with candidate campaigns.
In early April, the group revealed to the New York Times that in order to maintain GOP control of the Senate, it plans to spend around $350 million in 2026 on television, digital and streaming ads, as well as mail and other operations to influence voter turnout. The Times reported that the super PAC is prioritizing defending five Republican-held seats by spending $79 million in Ohio, $71 million in North Carolina, $42 million in Maine, $29 million in Iowa and $15 million in Alaska. In addition, the group is looking to flip three Democratic seats by spending $45 million in Michigan, $44 million in Georgia and $17 million in New Hampshire.
Ads in those races are set to start airing in September, the Times said. Democrats need to gain a net of four seats to regain the majority in the Senate (including the two independent senators who caucus with the Democrats).
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. At that point, it still had $238.6 million in cash on hand – more than double the amount it had at the same point in 2024, according to a press release.
Some of SLF PAC’s largest individual donors for this election cycle include Miriam Adelson, a physician and businesswoman; Paul Elliott Singer, a hedge fund manager; and Elon Musk, the wealthiest person in the world. It has also received at least $46 million, so far, from an affiliated nonprofit, One Nation, a so-called “dark money” group that, as a registered 501(c)(4) organization, does not have to disclose its donors. One Nation is led by Steven Law, who headed the Senate Leadership Fund until he stepped down in 2024.
During the 2024 election cycle, SLF PAC spent $211 million on independent expenditures — the third most of any super PAC (only exceeded by Make America Great Again Inc. and WinSenate PAC), according to an analysis of campaign finance data by OpenSecrets. The FEC defines independent expenditures as spending on communications that “expressly advocate” for the election or defeat of a specific candidate.
OpenSecrets said roughly 71% of that money was spent backing candidates who won their races or opposing candidates who lost. About 30% of SLF PAC’s independent expenditure dollars in 2024 were spent opposing the reelection of then-Sen. Sherrod Brown of Ohio, a Democrat, and supporting his Republican challenger, Bernie Moreno. Brown had been a three-term senator before being ousted by Moreno.
SLP PAC is planning to spend big in Ohio again in 2026, as Brown is now challenging Republican Sen. Jon Husted, who was appointed to fill the seat vacated in early 2025 by Vice President JD Vance.
FactCheck.org Undergraduate Fellow Christine Sung contributed to this article.
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