Janet Mills Ends Senate Bid as Grassroots Insurgent Graham Platner Surges in Maine Primary

Key facts

• Maine Gov. Janet Mills, 77, launched her Senate campaign in October 2024.
• She ended her campaign on Thursday, weeks before the June 9 primary.
• Graham Platner, an oyster farmer and military veteran, had been drawing large crowds and raising impressive sums.
• Platner received early endorsements from Sen. Bernie Sanders and Rep. Alexandria Ocasio-Cortez.
• Mills had backing from Senate Minority Leader Chuck Schumer and Senate Democratic leadership.
• Platner’s past social media posts denigrating police and rural White Americans surfaced, which he disavowed.
• The primary contest reignited debate over Senate Democratic leaders’ involvement in intraparty battles.

A Veteran Governor Steps Aside

Maine Gov. Janet Mills ended her Senate campaign on Thursday, conceding to a tide of grassroots energy that she and her establishment backers had underestimated. The 77-year-old Democrat, who launched her bid in October, cited difficulties raising money as the primary reason for her withdrawal, which came weeks before the June 9 primary. Mills’s decision revealed a broader trend within the Democratic Party: primary voters are increasingly spurning seasoned politicians in favor of untested outsiders who promise a more aggressive posture toward President Donald Trump. Her departure leaves Graham Platner, a 40-year-old oyster farmer and military veteran, as the likely nominee to challenge Republican Sen. Susan Collins.

The Rise of Graham Platner

By the time Mills entered the race, Platner had already built a formidable campaign, drawing large crowds and raising impressive amounts of money. He struck a chord with voters by railing against the ultra-wealthy, lambasting foreign entanglements, and calling for new Democratic leadership in Washington. Platner’s early momentum was bolstered by high-profile endorsements, including from independent Vermont Sen. Bernie Sanders, who warned against a Mills candidacy days before her launch. “We need to focus on winning that seat & not waste millions on an unnecessary & divisive primary,” Sanders wrote on X at the time. Rep. Alexandria Ocasio-Cortez of New York also praised Platner’s campaign, saying it reminded her of her own 2018 primary upset.

Establishment Support Falls Short

Mills’s campaign had the backing of Senate Minority Leader Chuck Schumer and other Senate Democratic leaders, who believed her statewide name recognition and a tidal wave of opposition research on Platner would secure her victory. They argued that Mills, a hardened political veteran, was best positioned to defeat Collins, who is seeking a sixth term in a state that Trump lost three times, including by 7 percentage points in 2024. But the strategy failed. Platner’s appeal as a generational change candidate and his ability to mobilize grassroots support overwhelmed Mills’s establishment advantages. The primary reignited debate over how much Senate Democratic leaders should be involved in intraparty battles, with Ocasio-Cortez saying Democrats can “certainly” learn from Platner’s success.

Controversy and Resilience

Despite his early momentum, Platner faced turbulence after Mills declared her candidacy, as multiple outlets reported on offensive comments he made on social media in the past. In some posts, Platner denigrated police and said rural White Americans “actually are” racist and stupid, according to a from last year. Platner has disavowed the posts, saying they do not reflect who he is today. His supporters, however, remained undeterred. State Rep. Valli Geiger expressed excitement about Platner’s improbable triumph, saying, “My feet aren’t even on the ground. I am so excited about today, not because our governor had to submit to the inevitable and suspend her campaign, but because of what it says about the politics of what is possible.”

The Battle for Maine’s Senate Seat

Democrats have long targeted Maine as a key pickup opportunity to retake the Senate majority in November. Collins has outlasted national headwinds before, but the state’s shifting demographics and Trump’s unpopularity there have made the race competitive. Platner now faces the challenge of uniting the party and taking on Collins, a formidable incumbent. His campaign’s strong focus on in-person events and anti-establishment message could resonate with voters disillusioned by traditional politics. However, the controversy over his past comments may provide ammunition for Republican attacks.

What Comes Next

With Mills out of the race, Platner is the de facto Democratic nominee, though the primary ballot has not yet been finalized. He struck a gracious tone in response to Mills’s withdrawal, applauding her long record of public service and their shared dedication to defeating Collins. Some of Platner’s supporters were openly ecstatic about his victory over Mills, viewing it as a sign that the party is ready for new leadership. The general election campaign will test whether Platner can broaden his appeal beyond the progressive base and withstand the scrutiny that comes with a high-profile Senate race.

The bottom line

• Janet Mills ended her Senate campaign due to fundraising difficulties, clearing the path for Graham Platner.
• Platner’s grassroots campaign and endorsements from Sanders and Ocasio-Cortez propelled him past the establishment-backed Mills.
• The primary outcome reflects a Democratic shift toward outsiders who promise a more confrontational stance against Trump.
• Platner’s past controversial social media posts have surfaced but he disavowed them, and his supporters remain loyal.
• Maine’s Senate race is a key battleground for Democrats seeking to retake the majority, with incumbent Susan Collins seeking a sixth term.
• The general election will test Platner’s ability to unite the party and withstand attacks over his past comments.