Former Senator Joe Manchin endorsed Republican incumbent Susan Collins for reelection in Maine, bucking Senate Democratic Leader Chuck Schumer and providing a major boost to the veteran moderate as both parties battle for Senate control.

Former Democrat Crosses Party Lines

Manchin, who left the Democratic Party in May 2024 to register as an independent, announced his support for Collins during a CNBC appearance Monday. The endorsement places a former Democratic senator squarely behind a Republican incumbent in one of the most closely watched Senate races of the 2026 cycle.

Collins faces a challenge from Troy Jackson, a progressive Democrat who wants her seat. The Maine senator has held her position since 1997 and has built a reputation as a moderate Republican willing to break with her party on key issues.

Independent Leadership Council Strategy

Since leaving office in January 2025 after representing West Virginia for more than 14 years, Manchin has helped launch the Independent Leadership Council. The initiative supports candidates who run outside the two major parties or who demonstrate independence from rigid party orthodoxy.

Manchin's endorsement fits his broader political strategy of elevating pragmatic centrists over partisan ideologues. During his Senate tenure, he was known as the chamber's most conservative Democrat, frequently frustrating party leadership with his willingness to vote against Democratic priorities.

Significant Boost for Collins

The endorsement provides Collins with a notable credential as she works to appeal to independent and moderate Democratic voters in Maine. The state has a strong independent streak, with voters often splitting tickets and rewarding candidates who demonstrate bipartisan credentials.

Collins has carefully cultivated her moderate image throughout her Senate career, occasionally breaking with Republican positions on healthcare, abortion rights, and other social issues. Her voting record places her among the Senate's most centrist members.

Democrats Face Tough Maine Fight

Jackson, the Democratic challenger, represents a more progressive wing of the party. His campaign has focused on economic populism and criticism of Collins' votes on judicial nominations and tax policy. However, unseating Collins has proven difficult for Democrats in previous cycles.

The moderate lane in Maine politics has historically been productive ground for Collins. With Manchin's endorsement reinforcing her independent credentials, she gains ammunition to argue she represents a bipartisan approach rather than rigid party loyalty.

Schumer and Senate Democrats had hoped to consolidate support behind Jackson as they work to maintain their narrow majority. Manchin's decision to support Collins over the Democratic nominee represents a significant setback to those efforts and highlights ongoing tensions between the party's moderate and progressive factions.