Key GOP-aligned war chest overflowing with cash as midterms loom

A top super PAC supporting Senate GOP candidates set a new fundraising record in the first half of 2025, building on expectations that Senate Republicans will attempt to expand their three-seat majority during the midterms.

The Senate Majority Leader John Thune-aligned Senate Leadership Fund (SLF) and its affiliated advocacy group, One Nation, have raised $85 million since January — more than double the super PAC raised at the same point in 2023. The massive fundraising haul comes as Senate Republicans are looking to defend and grow their majority in 2026 and sell the public about the contents of President Donald Trump’s One Big Beautiful Bill Act, which the Senate passed by a narrow margin Wednesday and Trump signed into law two days later.

The groups’ record-breaking fundraising haul is the first fundraising period since Thune succeeded Republican Kentucky Sen. Mitch McConnell as Senate Republican Leader in January. Axios was first to report the SLF and its affiliates’ eye-grabbing earnings in the first half of 2025.

The Thune-aligned groups have already begun spending in five battleground states — Georgia, North Carolina, Maine, Alaska and Nebraska — according to Axios.

Republican groups are expected to spend aggressively to defeat Democratic Georgia Sen. Jon Ossoff, who is viewed as the most vulnerable Democratic incumbent running for reelection. Ossoff, who represents a state that Trump carried in November, has routinely voted against Trump-backed legislation, including the president’s tax and immigration bill, and has signaled support for the president’s impeachment.

No well-known candidate has yet to enter the North Carolina contest following Republican Sen. Thom Tillis’ surprise announcement to not seek reelection. However, Trump said he would back his daughter-in-law, Lara Trump, if she decides to make a run for the open Senate seat.

Lara Trump, who hosts a Saturday evening program on Fox News, interviewed Thune about Senate Republicans’ work implementing the president’s agenda in May and has previously weighed a Senate run.

SLF and its affiliates are also expected to aggressively defend Republican Maine Sen. Susan Collins’ seat. The five-term incumbent has yet to announce whether she will run for reelection.

The campaign juggernaut will begin making ad buys in Texas in support of Republican Texas Sen. John Cornyn, according to Axios. The Republican incumbent is trailing Republican Texas Attorney General Ken Paxton by double digits nine months ahead of primary election night, according to recent polling.

Thune and National Republican Senatorial Campaign Chairman Tim Scott of South Carolina have endorsed Cornyn’s reelection bid.

SLF and its affiliate groups are also expected to build support for Trump’s landmark bill in competitive states during the lead-up to the midterms.

A majority of voters in battleground states support key provisions in Trump’s signature bill, according to recent polling commissioned by One Nation. The survey found that just 12% of likely voters in Georgia, Maine, Michigan and North Carolina opposed a permanent extension of the 2017 Trump tax cuts and the president’s other tax relief items when branded as a “working family tax cut.”

Thune, prior to the bill’s passage, told the Daily Caller News Foundation that he hoped Senate Republicans and national GOP groups would go on offense in touting the benefits of the legislation.

“When you start breaking it down and you look at these items, they’re enormously popular,” Thune told the DCNF in a June interview. “I’m hoping that our members will get out there and start messaging aggressively on that, because I think it’ll win the hearts and minds of the American people.”