WASHINGTON — Several Democratic senators broke with Senate Minority Leader Chuck Schumer and the Democratic Senatorial Campaign Committee by endorsing independent candidate Graham Platner over Gov. Janet Mills in Maine's 2026 U.S. Senate race.

Schumer and the DSCC endorsed Mills, Maine's second-term governor. But senators including Martin Heinrich, Elizabeth Warren, and Bernie Sanders backed Platner, a veteran and oyster farmer who launched his Senate campaign.

"Clearly there's a disagreement of strategy here," said U.S. Senator Martin Heinrich, who also held a fundraiser for Platner along with Senator Sheldon Whitehouse.

Democratic strategist Lis Smith said the endorsements reflected broader dissatisfaction with Schumer's leadership. "Endorsements in races like Maine and Michigan are as much a rebuke of Schumer as they are an endorsement of these candidates." She said "It's pretty uncommon for sitting senators to endorse against the Senate leader."

The public split over the Maine race followed other points of contention within the Democratic caucus. In March 2025, Schumer voted with Republicans to end a government shutdown. Some Democrats criticized Schumer for not pushing hard enough against former President Donald Trump's agenda. Later in 2025, Democrats maintained firm opposition during a record-long government shutdown fight, the longest in U.S. history. But a group of moderate Democrats subsequently sided with Republicans in another shutdown fight, a move Schumer opposed.

Schumer became Senate Democratic leader in 2017 and has overseen mixed electoral results. Democrats regained the Senate majority in 2020 and expanded it in 2022 under his leadership, but lost seats in both 2018 and 2024.

Schumer's spokesperson Allison Biasotti defended his leadership. "Leader Schumer's North Star is taking back the Senate and is pursuing a path to do just that."

DSCC communications director Maeve Coyle said "He created a path to win a Democratic Senate majority this cycle." Coyle added that "Senate Democrats overperformed in the last four election cycles and in 2026, we will win seats and flip the majority."

U.S. Senator Tina Smith, discussing her own endorsement decisions, said "She understands that right now what we need are fierce fighters, people who are willing to stand up to the status quo."