By Anvee Bhutani

WASHINGTON -- A group aligned with Senate Majority Leader John Thune (R., S.D.) is planning to spend tens of millions of dollars to protect centrist Sen. Susan Collins of Maine in this year's midterms, even as President Trump has repeatedly criticized her for breaking with the party.

The Senate Leadership Fund super PAC plans to spend $40 million on TV, radio and digital ads, along with data and get-out-the-vote activities from August through Election Day in Maine. SLF says it is its first ad reservation of the cycle and its largest-ever investment in Maine.

Republicans hold a 53--47 Senate majority. Maine is considered one of the most competitive seats Republicans are defending in this year's midterms, along with North Carolina. Democrats are also eyeing Ohio and Alaska, while Republicans are aiming to flip Michigan and Georgia.

The Maine race has grabbed more attention this month after Trump publicly criticized Collins for her vote with Democrats to limit presidential war powers in Venezuela, saying she and other holdouts "should never be elected to office again." In separate remarks, he referred to Collins and fellow centrist Sen. Lisa Murkowski (R., Alaska) as "disasters." Trump's admonishments underscore growing tensions between Collins's independent streak and the more hard-line elements of the GOP base.

"Collins is the only Republican candidate that can win Maine," Alex Latcham, executive director of the Senate Leadership Fund said in an interview. "She is critical to maintaining the Senate majority and we will be there for her. "

In 2020, Collins defeated Democrat Sara Gideon by about 9 percentage points, even as Trump lost Maine in the presidential contest.

Trump could be a decisive figure in setting the GOP field. Over the weekend, he endorsed a challenger to current GOP Sen. Bill Cassidy of Louisiana, who voted with Democrats and a handful of other Republicans to convict him on an impeachment count in 2021. Trump backed Rep. Julia Letlow -- who announced her candidacy Tuesday morning -- in the Republican primary. Thune has endorsed Cassidy and hosted a fundraiser for him last week in Louisiana.

"The mission of Senate Leadership Fund is to preserve and expand the Republican Senate majority," Latcham said about the Letlow endorsement. "Anything that distracts from our efforts to beat Democrats in November is unhelpful."

Trump had alerted Thune that he was likely to endorse Letlow, but Thune counseled Trump that he should back Cassidy instead, according to people familiar with the matter.

For over two decades, Collins has positioned herself as a centrist Republican, sometimes breaking with her party in high-profile policy battles.

Democrats running for the seat include Gov. Janet Mills, backed by Senate Minority Leader Chuck Schumer (D., N.Y.) and political newcomer Graham Platner, who has been endorsed by progressive icon Bernie Sanders (I., Vt.).

Federal Election Commission data shows some outside-groups have begun to spend in Maine, but Election Day is still over nine months away and Democrats and their allied super PACs haven't yet begun targeting Collins with aggressive media buys of their own.

Write to Anvee Bhutani at anvee.bhutani@wsj.com

(END) Dow Jones Newswires

January 20, 2026 12:09 ET (17:09 GMT)

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