New Ballot Exhibits Democrat Senate Candidate Graham Platner Crushing Republican Susan Collins
A new statewide poll suggests Maine’s 2026 U.S. Senate race could take a dramatically different shape depending on which Democrat emerges from the primary, with Democratic candidate Graham Platner posting the strongest early numbers against Republican Sen. Susan Collins.
The poll from Quantus Insights offers an early snapshot of the political landscape as Democrats begin sorting out their nominee. While Collins remains competitive against Democratic Gov. Janet Mills, the numbers shift noticeably when the matchup includes Platner, suggesting the race could take on a different dynamic depending on who ultimately secures the Democratic nomination.
In a hypothetical matchup between Collins and Mills, the race appears extremely close. The poll shows Collins receiving 44.6 percent of the vote compared with 43.0 percent for Mills.
Third-party candidates account for 5.6 percent, while another 5.6 percent remain undecided. An additional 1.1 percent said they would not vote. The numbers reflect the familiar political pattern that has defined Maine’s statewide contests for years, with Collins maintaining a durable base of Republican support while continuing to attract some independents and moderate Democrats.
A contest between Collins and Mills would likely become a referendum on two well-established political figures who are already deeply familiar to voters across the state. Collins has served in the Senate since 1997 and has repeatedly won reelection by building a coalition that extends beyond the Republican base.
Mills, who has served as Maine’s governor since 2019, similarly carries strong name recognition and a well-developed political network. Early polling suggests neither candidate begins with a decisive advantage in that scenario.
NEW: Quantus Insights Maine Senate Race | March 9, 2026
General Election:
Collins vs Mills
🔴 Collins: 44.6%
🔵 Mills: 43%Collins vs Platner
🔵 Platner: 48.6%
🔴 Collins: 41.8%
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Democrat Primary
🔵Platner: 43.3%
🔵Mills: 38%
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Susan Collins… pic.twitter.com/FBE4sWmij9— Quantus Insights (@QuantusInsights) March 9, 2026
The picture changes significantly when Collins is paired with Democratic candidate Graham Platner. In that head-to-head matchup, Platner leads with 48.6 percent support, compared with 41.8 percent for Collins. Another 5.9 percent remain undecided, while 2.9 percent support a third-party candidate and 0.9 percent say they would not vote. The nearly seven-point advantage suggests Platner may be benefiting from a different coalition of voters than Mills, including some who appear more open to a newer Democratic figure in the race.
Several factors could help explain the early gap. Platner currently has lower statewide name recognition than Mills, which can sometimes work to a candidate’s advantage early in a campaign because voters have not yet formed strong opinions.
At the same time, the results suggest that some voters who might hesitate to support the sitting governor may be more open to backing a different Democratic nominee. Whether that early lead would hold through a full general election campaign would likely depend on how both candidates are defined in the months ahead.
The Quantus Insights survey also examined the Democratic primary, where Platner currently holds a modest lead over Mills among Democratic voters. The poll shows Platner receiving 43.3 percent support, compared with 38.0 percent for Mills, while 18.7 percent remain undecided. With nearly one in five voters still making up their minds, the primary contest remains fluid and could shift significantly as the campaign unfolds.
Platner has already begun drawing attention through campaign activity. Over the weekend, he held an anti-war protest outside Collins’ office criticizing U.S. military action against Iran.
Maine voters appear politically divided, with a sizable share of the electorate still undecided or open to alternative candidates. The results also suggest the identity of the Democratic nominee could play a major role in shaping the general election contest.
With the Democratic primary still developing and months of campaigning ahead, the Quantus Insights survey provides only an early look at a race that could evolve considerably before Maine voters head to the polls in 2026.