AUGUSTA, Maine — An increasingly bruising Democratic primary to challenge Republican Sen. Susan Collins has turned into an expensive, high-stakes fight between Maine Gov. Janet Mills and combat veteran–turned–oyster farmer Graham Platner, even as Collins has spent little on her own reelection so far.
The outcome matters for Democrats’ longshot effort to flip the U.S. Senate this year. With the June 9 primary more than two months away, Mills and Platner have engaged in a proxy battle between establishment and insurgent wings of the party while outside Republican groups marshal large resources to return Collins to the Senate for a sixth term.
Two competing claims to electability
Mills, recruited by Senate Minority Leader Chuck Schumer, argues she is the safer bet to defeat Collins after winning two statewide races. Platner, who launched his campaign earlier, quickly won Sen. Bernie Sanders’s endorsement and has energized crowds with a message that criticizes Washington Democrats for abandoning working-class Mainers and relying on “the same old, tired playbook.”
Platner’s campaign initially sputtered after media reports in October surfaced old offensive social media posts and a tattoo mirroring Nazi imagery; he later acknowledged both. Despite that, polls from the University of New Hampshire Survey Center and Pan Atlantic SMS have shown Platner leading in the Democratic primary.
Mills has seized on Platner’s past comments in recent advertising, focusing on a 2013 Reddit post about a website promoting locking underwear for women. The governor’s ad features women reacting to a passage in the post that included the line, “How about people just take some responsibility for themselves and not get so f***ed up they wind up having sex with someone they don’t mean to?”
Platner responded with a media event featuring women who support him and apologized, attributing the posts to the anger and disillusionment he experienced after combat tours in Iraq and Afghanistan. “When I read through my old internet posts when they resurfaced six months ago, I was horrified,” he said. “I did not recognize in them myself or the man that I am today. I did not recognize myself in this person that was struggling to find meaning and posted awful things 13 years ago. I am sorry, but it does not in any way reflect who I am today, or the beliefs that I hold.” His campaign also ran a direct-to-camera TV spot responding to Mills’s ad.
Spending dynamics: Democrats spend on each other, Republicans on Collins
So far Platner has outspent Mills on advertising and outraised her overall. AdImpact data show Platner spending about $4.2 million on advertising versus Mills’s $1.16 million in the same tracking period. Federal Election Commission filings through last year show Platner’s campaign fundraising nearly three times Mills’s totals.
Much of Democratic-aligned outside spending has concentrated on attacking Collins rather than backing either primary candidate. Collins herself has spent roughly $240,000 on the race to date. But outside Republican groups, most notably One Nation, have been prolific: One Nation — operating as an issue advocacy group that shields its donors — has spent just over $10 million so far on ads, web outreach, texts and mailers highlighting Collins’s record securing federal funding, a theme that helped her in 2020.
Political scientists and strategic trade-offs
Ron Schmidt, a political science professor at the University of Southern Maine, says early spending by both Mills and Platner makes strategic sense: Platner needs to introduce himself to voters statewide; Mills aims to define him before the primary. Her attack ads are a direct appeal to female voters she hopes will support her in the primary and then help defeat Collins in the general election. But Schmidt warns those attacks risk alienating Platner’s supporters and weakening Democratic unity in a potential general election matchup.
Mills frames her case on electability and confrontation with former President Donald Trump, saying it is “important that Maine voters hear Platner’s own words and the absolutely abhorrent things that he has said.” Platner calls the attacks an effort by the Democratic establishment to destroy his candidacy. “It takes political courage to come out against those in power and it is not lost on me what this means,” he said after thanking supporters.
With Collins largely letting others do the spending heavy lifting, the primary is likely to continue as a costly, adversarial contest that Democrats must reckon with if they hope to consolidate behind a single challenger in November.