Former Sen. Joe Manchin, a Democrat from West Virginia, endorsed Republican Sen. Susan Collins of Maine for reelection Monday, praising her role in the Senate and her willingness to work across party lines. Manchin said that losing Collins from the Senate would mean “losing the soul of the Senate” and described her as someone who is “always in the trenches.”

Manchin and Collins served together in the Senate and worked across party lines on issues including energy, health care and rural policy. Their bipartisan relationship has continued to draw attention as Collins seeks a sixth term in a state that has consistently backed Democratic presidential candidates in recent elections.

Sen. Collins responded to the announcement in an X post. In it, she called Manchin a "dear friend and trusted colleague" that she has consistently worked with "to solve problems and deliver results for the people of Maine and America."

Collins will face Democratic nominee Troy Jackson in the November general election. Jackson, a former Maine Senate president and longtime state lawmaker, became the Democratic nominee after previous Democrat nominee Graham Platner withdrew from the race in July following scrutiny over an allegation of sexual assault. A Democratic nominating convention selected Jackson as Platner's replacement.

Jackson has campaigned as a working-class Democrat and has criticized Collins over her long tenure in Washington and her relationship with President Donald Trump. Collins, meanwhile, has emphasized her record of bipartisan legislation and her position as chair of the Senate Appropriations Committee, which gives her a role in determining federal spending.

Manchin's endorsement comes as Collins faces one of the closely watched Senate contests of the 2026 election cycle. She is the only Republican senator representing a New England state and is defending a seat in a state that voted for Kamala Harris over Trump in the 2024 presidential election.