Union Leaders Urge Schumer, DSCC To Withdraw Support For Janet Mills Amid Maine Senate Primary Rift

Union officials have privately pressed Senate Minority Leader Chuck Schumer and the Democratic Senatorial Campaign Committee (DSCC) to withdraw their support for Maine Gov. Janet Mills in the state's Democratic Senate primary, arguing her labor record is weaker than that of challenger Graham Platner.

Labor Pushes Back

United Auto Workers President Shawn Fain spoke with Schumer this month about the Maine contest and other issues, according to sources who spoke with NBC News. The UAW has endorsed Platner, while Schumer and the DSCC have publicly backed Mills. One source said Fain used the call to highlight what he sees as Democratic leaders' failure to listen to working-class voters and cited the Maine race as an example.

On Monday, Michael Monahan, international vice president of the International Brotherhood of Electrical Workers' 2nd District, which includes Maine, sent a letter to DSCC leadership obtained by NBC News urging the committee to "refrain from intervening further in this primary." Monahan described Mills' relationship with organized labor as "fraught" and said his membership is troubled by the DSCC's support for her.

Polls, Endorsements And Concerns

A University of New Hampshire poll in mid-February showed Platner leading Mills by 38 points among likely Democratic primary voters — a margin Mills' campaign disputed, saying the survey skewed younger than Maine's typical electorate. Labor leaders warn that DSCC spending against Platner could weaken him ahead of a potential general election against Republican Sen. Susan Collins, even as the national party argues Mills is the stronger general-election candidate.

Gov. Janet Mills has the backing of the Democratic Senatorial Campaign Committee. (Robert F. Bukaty / AP file)(Robert F. Bukaty)

Platner, an oyster farmer and military veteran who announced his campaign in August, has faced controversies: he apologized for offensive posts on Reddit and said he covered a chest tattoo with a Nazi association that he claimed he did not recognize when he got it. Despite that, he has drawn numerous union endorsements, including from the UAW, the International Association of Machinists and Aerospace Workers, the Maine affiliate of National Nurses United, and others. He has also been endorsed by Sens. Bernie Sanders (I‑Vt.), Chris Murphy (D‑Conn.) and Sheldon Whitehouse (D‑R.I.).

“So I called my people in D.C. and said, ‘Schumer needs to stay out of Maine,’” said David Sullivan, general vice president for the International Association of Machinists’ eastern territory. “They said they were going to stick by their guns and they were going to put millions of dollars in for Janet Mills. … We’re going to fight this all the way.”

Mills' Record And The DSCC Defense

Mills' campaign pointed to pro-labor measures she has backed as governor, citing work to increase the minimum wage, strengthen worker safety standards and protect employees from retaliation for reporting labor-law violations. Mills also received a 2022 endorsement from the Maine AFL‑CIO. Her campaign emphasized her record of negotiating and passing legislation they say delivers results for Mainers.

The DSCC has publicly promoted Mills as a strong recruit to flip a Republican-held seat and has joined her campaign's joint fundraising committee. DSCC Chair Sen. Kirsten Gillibrand argued that Mills is uniquely positioned to take on Sen. Susan Collins and win.

What’s At Stake

The June 9 primary highlights broader generational and ideological divides within the Democratic Party. Democrats view the Maine seat as one of their best opportunities to flip a Republican Senate seat in 2026, making the outcome of the primary significant for both labor allies and national party strategists.

Schumer and the DSCC did not respond to requests for comment for this report.