2026 United States Senate election in Maine

2026 United States Senate election in Maine

The 2026 United States Senate election in Maine will be held on November 3, 2026, to elect a member of the United States Senate to represent the state of Maine. Incumbent Republican Senator Susan Collins, first elected in 1996, is running for re-election to a sixth term in office. If elected, Collins will become the longest-serving U.S. Senator from Maine, surpassing William P. Frye on May 26, 2027.

This will be the only Republican-held Senate seat up for election in 2026 in a state that Kamala Harris won in the 2024 presidential election. Collins is the only incumbent Republican senator in any of the 19 states that Donald Trump did not win in any of his three elections. Both the Democratic primary and general election are expected to be some of the most competitive races in the Senate election cycle.

This election will coincide with U.S. House elections for Maine's two congressional districts, a gubernatorial election, and various other state, county and local elections. The primary is scheduled to take place on June 9, 2026. Both the primary and general elections will be conducted with ranked-choice voting.

Background

2026 United States Senate election in Maine

The northernmost state in New England, Maine is one of the most rural states in the nation, and is considered to be a moderately blue state, having voted for every Democratic presidential nominee since (/wiki/1992UnitedStatespresidentialelectioninMaine), and voting for Kamala Harris by about seven percentage points in (/wiki/2024UnitedStatespresidentialelectioninMaine). Democrats also control the governorship, the state legislature, and both seats in Maine's U.S. House congressional delegation. Furthermore, after Jared Golden defeated Bruce Poliquin in Maine's 2nd congressional district in (/wiki/2018UnitedStatesHouseofRepresentativeselectionsinMaine), Collins has been the only Republican representing any state in New England at the federal level, in either chamber of Congress.

Collins was first elected in (/wiki/1996UnitedStatesSenateelectioninMaine), and was re-elected in four subsequent elections, significantly outperforming other Republicans in the state. In (/wiki/2020UnitedStatesSenateelectioninMaine), despite almost all polls and analysts predicting that she would lose her re-election bid, Collins unexpectedly defeated Democratic nominee Sara Gideon by about nine percentage points. Democratic presidential nominee Joe Biden carried Maine by about nine percentage points on the same ballot.

As the only Republican-held Senate seat up for election in a state won by Kamala Harris in the 2024 presidential election, Maine is considered a key Senate battleground in 2026 despite Susan Collins’ history of electoral overperformance. Republicans have held the seat since 1979, when William Cohen defeated incumbent Democrat William Hathaway—the last time a sitting U.S. senator from Maine lost reelection. No Democrat has won a Maine Senate race since George J. Mitchell was reelected in (/wiki/1988UnitedStatesSenateelectioninMaine), or this seat since Hathaway’s election in (/wiki/1972UnitedStatesSenateelectioninMaine).

With the decline of ticket splitting, and being in a midterm election with an unpopular Republican president, Collins is widely viewed as the most vulnerable incumbent Republican senator. Following the retirement of Joe Manchin in West Virginia, and the defeats of Democratic senators Jon Tester in Montana and Sherrod Brown in Ohio in (/wiki/2024UnitedStatesSenateelections), Collins remains the last senator to represent a non-swing state of the opposite party (a reliably red or blue state).

Republican primary

2026 United States Senate election in Maine

Incumbent U.S. senator Susan Collins officially announced her reelection bid in February 2026. Despite conservative backlash to her centrist voting record, the Republican Party has supported her reelection. However, she faced a primary challenge from former police officer Dan Smeriglio, a critic of her bipartisan approach. Ultimately, Collins was the only Republican to qualify for the primary ballot.

Presumptive nominee

• Susan Collins, incumbent U.S. senator (1997–present)

Withdrawn

• Carmen Calabrese, restaurant owner • Bill Clarke, entrepreneur and Constitution Party nominee for U.S. Senate in (/wiki/1996UnitedStatesSenateelectioninMaine) and for governor in (/wiki/1998Mainegubernatorialelection) • Dan Smeriglio, former police officer

Fundraising

Campaign finance reports as of December 31, 2025
Candidate	Raised	Spent	Cash on hand
Carmen Calabrese (R)	$17,760	$21,260	$0.00
Susan Collins (R)	$10,153,542	$3,409,501	$8,039,234
Source: Federal Election Commission

Polling

Poll source	Date(s) administered	Sample size	Margin of error	Carmen Calabrese	Susan Collins	Dan Smeriglio	Other	Undecided
	March 1, 2026	Calabrese withdraws
University of New Hampshire	February 12–16, 2026	417 (LV)	± 4.9%	1%	67%	6%	1%	25%
University of New Hampshire	October 16–21, 2025	417 (LV)	± 4.8%	1%	66%	1%	4%	27%

Democratic primary

Campaign

In April 2025, former congressional staffer Jordan Wood became the first Democrat to enter the race, running on a platform opposed to the Trump administration and Elon Musk. On August 19, Sullivan Harbor Master Graham Platner launched a progressive campaign backed by Bernie Sanders and organized labor, positioning himself against the “Democratic establishment” and drawing support from both liberal voters and some 2024 Trump voters.

Governor Janet Mills was widely viewed as a top Democratic recruit, with encouragement from national figures including Senate Minority Leader Chuck Schumer, Senator Kirsten Gillibrand, and the Democratic Senatorial Campaign Committee (DSCC), though Sanders publicly discouraged her candidacy. After weeks of speculation and leaked campaign plans, Mills entered the race in October 2025, pledging to serve only one term; her age, 79 at the start of the term, drew some scrutiny. The DSCC’s close involvement in her campaign, including a joint fundraising committee, prompted backlash and allegations of favoritism in the primary.

Following her entry, several candidates, including Dan Kleban and Daira Smith-Rodriguez, withdrew and endorsed Mills. Smith-Rodriguez cited concerns over past comments by Platner regarding sexual assault in the military. Wood later withdrew to run for the U.S. House.

In January 2026, Platner briefly paused his campaign due to his wife’s medical treatment abroad before resuming later that month, returning to the trail with protests against Immigrations and Customs Enforcement (ICE) enforcement actions.

By early 2026, Mills committed to multiple debates ahead of the June 9 primary, while Platner secured endorsements from Senators Martin Heinrich, Elizabeth Warren, and Ruben Gallego, the latter of whom also questioned Mills’ general election viability.

Although several Democrats initially filed, only Mills, Platner, and 2024 nominee David Costello qualified for the primary ballot. In addition, University of Maine adjunct professor Andrea LaFlamme is mounting a write-in bid for the Democratic nomination.

Despite multiple controversies, polling has consistently shown Platner leading Mills in the primary and incumbent Senator Susan Collins in a potential general election matchup.

Controversies

Shortly after Mills entered the race, Platner came under fire for resurfaced controversial Reddit posts, resulting in his campaign's political director, former state representative Genevieve McDonald, quitting the campaign and calling Platner "unelectable"; however, Democratic National Committee Chair Ken Martin stated that the comments were not disqualifying, and Platner apologized in a five-minute video posted to social media. On October 21, Platner released a video of himself dancing and singing shirtless at his brother's wedding, revealing he had a chest tattoo that resembled the Totenkopf used by Nazi Germany's Schutzstaffel. Platner stated he got the tattoo while inebriated with other U.S. Marines while stationed in Croatia, mistaking the symbol for a generic skull and crossbones. He had the tattoo covered, and professed his shame and disgust for getting a tattoo that resembled the fascist insignia. Platner also called himself an anti-fascist "supersoldier" in an old Reddit comment. After the controversies, Democrats such as Senator Chris Murphy defended Platner and said that he "sounds like a human being" who is honest about his mistakes and Senator Gallego called his campaign "authentic" and said that he has "the right to grow out of his stupidity" and is not going to be a "crypto Fetterman".

On February 26, 2026, Platner quote-tweeted a clip from Donald Trump's 2026 State of the Union Address, criticizing Trump's speech. The clip had been posted by anti-Semitic white supremacist Stew Peters. The tweet was deleted hours later, with a spokesperson for Platner's campaign telling The Hill that they were unaware of Peters' views.

Declared

• David Costello, former deputy secretary of the Maryland Department of the Environment and nominee for U.S. Senate in (/wiki/2024UnitedStatesSenateelectioninMaine) • Andrea LaFlamme, adjunct professor at the University of Maine (write-in candidate) • Janet Mills, governor of Maine (2019–present) • Graham Platner, Sullivan harbor master

Withdrawn

• Natasha Alcala, fashion designer • David Evans, former Department of Defense policy writer • Tucker Favreau, cybersecurity professional • Dan Kleban, brewery owner (endorsed Mills) • Daira Smith-Rodriguez, former civilian contracting officer for the U.S. Air Force (endorsed Mills) • Jordan Wood, former chief of staff to former U.S. Representative Katie Porter (running for U.S. House)

Declined

• Aaron Frey, Maine attorney general (2019–present) (endorsed Mills) • Jared Golden, U.S. representative from Maine's 2nd congressional district (2019–present) • Chellie Pingree, U.S. representative from Maine's 1st congressional district (2009–present) and nominee for U.S. Senate in (/wiki/2002UnitedStatesSenateelectioninMaine) (running for re-election)

Fundraising

Campaign finance reports as of December 31, 2025
Candidate	Raised	Spent	Cash on hand
David Costello (D)	$101,764	$13,906	$87,858
Tucker Favreau (D)	$10,083	$4,913	$5,170
Dan Kleban (D)	$458,779	$364,476	$94,304
Janet Mills (D)	$2,706,692	$1,396,412	$1,310,281
Graham Platner (D)	$7,867,908	$4,150,630	$3,717,278
Daira Smith-Rodriguez (D)	$242,582	$242,582	$0
Jordan Wood (D)	$3,098,912	$2,178,443	$920,470
Source: Federal Election Commission

Polling

Source of poll aggregation	Dates administered	Dates updated	Janet Mills	Graham Platner	Other/Undecided	Margin
Race to the WH	November 12, 2025 – March 23, 2026	March 31, 2026	31.2%	54.5%	14.3%	Platner +23.4%
RealClearPolitics	October 26, 2025 – March 23, 2026	March 26, 2026	32.8%	52.0%	15.2%	Platner +19.2%
Average	32.0%	53.3%	14.7%	Platner +21.3%

<table><thead><tr><th>Poll source</th><th>Date(s) administered</th><th>Sample size</th><th>Margin of error</th><th>David Costello</th><th>Janet Mills</th><th>Graham Platner</th><th>Jordan Wood</th><th>Other</th><th>Undecided</th></tr></thead><tbody><tr><td>Emerson College</td><td>March 21–23, 2026</td><td>530 (LV)</td><td>± 4.2%</td><td>1%</td><td>28%</td><td>55%</td><td>–</td><td>4%</td><td>13%</td></tr><tr><td>Impact Research (D)</td><td>March 19–23, 2026</td><td>500 (LV)</td><td>–</td><td>–</td><td>28%</td><td>66%</td><td>–</td><td>–</td><td>6%</td></tr><tr><td>Quantus Insights (R)</td><td>March 5, 2026</td><td>450 (LV)</td><td>± 3.4%</td><td>–</td><td>38%</td><td>43%</td><td>–</td><td>–</td><td>19%</td></tr><tr><td>Pan Atlantic Research</td><td>February 13 – March 2, 2026</td><td>367 (LV)</td><td>–</td><td>4%</td><td>39%</td><td>46%</td><td>–</td><td>–</td><td>11%</td></tr><tr><td>University of New Hampshire</td><td>February 12–16, 2026</td><td>462 (LV)</td><td>± 4.5%</td><td>1%</td><td>26%</td><td>64%</td><td>–</td><td>3%</td><td>6%</td></tr><tr><td></td><td>January 31, 2026</td><td>Favreau withdraws</td></tr><tr><td>Workbench Strategy (D)</td><td>December 11 – December 16, 2025</td><td>500 (LV)</td><td>–</td><td>–</td><td>40%</td><td>55%</td><td>–</td><td>–</td><td>5%</td></tr><tr><td>Pan Atlantic Research</td><td>November 29 – December 7, 2025</td><td>318 (LV)</td><td>–</td><td>1%</td><td>47%</td><td>37%</td><td>–</td><td>–</td><td>14%</td></tr><tr><td>Z to A Research (D)</td><td>November 14–18, 2025</td><td>845 (LV)</td><td>± 3.0%</td><td>0%</td><td>38%</td><td>58%</td><td>–</td><td>2%</td><td>2%</td></tr><tr><td></td><td>November 12, 2025</td><td>Wood withdraws</td></tr><tr><td>Maine People's Resource Center</td><td>October 26–29, 2025</td><td>783 (V)</td><td>± 3.5%</td><td>–</td><td>39%</td><td>41%</td><td>5%</td><td>–</td><td>14%</td></tr><tr><td>–</td><td>47%</td><td>53%</td><td>–</td><td>–</td><td>–</td></tr><tr><td>SoCal Strategies</td><td>October 21–25, 2025</td><td>500 (LV)</td><td>± 4.4%</td><td>1%</td><td>41%</td><td>36%</td><td>2%</td><td>–</td><td>20%</td></tr><tr><td>NRSC (R)</td><td>October 22–23, 2025</td><td>647 (LV)</td><td>± 3.5%</td><td>–</td><td>25%</td><td>46%</td><td>3%</td><td>–</td><td>26%</td></tr><tr><td>University of New Hampshire</td><td>October 16–21, 2025</td><td>510 (LV)</td><td>± 4.3%</td><td>1%</td><td>24%</td><td>58%</td><td>1%</td><td>1%</td><td>14%</td></tr></tbody></table>

Independents

Withdrawn

• Phillip Rench, former member of the Maine Space Corporation Board of Directors (2023–2025)

Fundraising

Campaign finance reports as of September 30, 2025
Candidate	Raised	Spent	Cash on hand
Phillip Rench (I)	$55,313	$31,072	$24,241
Source: Federal Election Commission

General election

Predictions

<table><thead><tr><th>Source</th><th>Ranking</th><th>As of</th></tr></thead><tbody><tr><td>Inside Elections</td><td>Tilt R</td><td>March 25, 2026</td></tr><tr><td>The Cook Political Report</td><td>Tossup</td><td>March 27, 2026</td></tr><tr><td>Sabato's Crystal Ball</td><td>Tossup</td><td>March 4, 2026</td></tr><tr><td>Race To The WH</td><td>Tossup</td><td>March 25, 2026</td></tr></tbody></table>

Polling

Source of poll aggregation	Dates administered	Dates updated	Susan Collins (R)	Janet Mills (D)	Other/Undecided	Margin
Race to the WH	October 7, 2025 – March 23, 2026	March 26, 2026	42.8%	43.8%	13.4%	Mills +1.1%
270toWin	February 24, 2026 – March 26, 2026	March 26, 2026	42.8%	43.2%	14.0%	Mills +0.4%
RealClearPolitics	February 12 – March 23, 2026	March 26, 2026	43.0%	43.5%	13.5%	Mills +0.5%
Average	42.9%	43.5%	13.6%	Mills +0.7%

<table><thead><tr><th>Poll source</th><th>Date(s) administered</th><th>Sample size</th><th>Margin of error</th><th>Susan Collins (R)</th><th>Janet Mills (D)</th><th>Other</th><th>Undecided</th></tr></thead><tbody><tr><td>Emerson College</td><td>March 21–23, 2026</td><td>1,075 (LV)</td><td>± 2.9%</td><td>43%</td><td>46%</td><td>8%</td><td>3%</td></tr><tr><td>OnMessage Public Strategies (R)</td><td>March 3–8, 2026</td><td>600 (LV)</td><td>± 4.0%</td><td>42%</td><td>42%</td><td>–</td><td>16%</td></tr><tr><td>Quantus Insights (R)</td><td>March 5, 2026</td><td>800 (LV)</td><td>± 3.4%</td><td>45%</td><td>43%</td><td>7%</td><td>6%</td></tr><tr><td>Pan Atlantic Research</td><td>February 13 – March 2, 2026</td><td>810 (LV)</td><td>± 3.7%</td><td>44%</td><td>44%</td><td>–</td><td>12%</td></tr><tr><td>University of New Hampshire</td><td>February 12–16, 2026</td><td>1,105 (LV)</td><td>± 2.9%</td><td>40%</td><td>41%</td><td>9%</td><td>10%</td></tr><tr><td>Fabrizio, Lee & Associates (R)</td><td>January 20–24, 2026</td><td>800 (LV)</td><td>± 3.5%</td><td>45%</td><td>44%</td><td>–</td><td>11%</td></tr><tr><td>Workbench Strategy (D)</td><td>December 11 – December 16, 2025</td><td>900 (LV)</td><td>±4.4%</td><td>51%</td><td>49%</td><td>–</td><td>–</td></tr><tr><td>Pan Atlantic Research</td><td>November 29 – December 7, 2025</td><td>820 (LV)</td><td>± 3.7%</td><td>43%</td><td>43%</td><td>–</td><td>14%</td></tr><tr><td>Maine People's Resource Center</td><td>October 26–29, 2025</td><td>783 (LV)</td><td>± 3.5%</td><td>46%</td><td>42%</td><td>–</td><td>14%</td></tr><tr><td>Zenith Research (D)</td><td>October 7–10, 2025</td><td>501 (LV)</td><td>± 4.4%</td><td>37%</td><td>42%</td><td>10%</td><td>12%</td></tr></tbody></table>

Source of poll aggregation	Dates administered	Dates updated	Susan Collins (R)	Graham Platner (D)	Other/Undecided	Margin
Race to the WH	October 7, 2025 – March 23, 2026	March 26, 2026	41.2%	46.2%	12.6%	Platner +5.0%
270toWin	February 24, 2026 – March 26, 2026	March 26, 2026	40.6%	46.8%	12.6%	Platner +6.2%
RealClearPolitics	February 12 – March 23, 2026	March 26, 2026	40.3%	47.5%	12.2%	Platner +7.2%
Average	40.7%	46.8%	12.5%	Platner +6.1%

<table><thead><tr><th>Poll source</th><th>Date(s) administered</th><th>Sample size</th><th>Margin of error</th><th>Susan Collins (R)</th><th>Graham Platner (D)</th><th>Other</th><th>Undecided</th></tr></thead><tbody><tr><td>Emerson College</td><td>March 21–23, 2026</td><td>1,075 (LV)</td><td>± 2.9%</td><td>41%</td><td>48%</td><td>6%</td><td>6%</td></tr><tr><td>OnMessage Public Strategies (R)</td><td>March 3–8, 2026</td><td>600 (LV)</td><td>± 4.0%</td><td>42%</td><td>44%</td><td>–</td><td>14%</td></tr><tr><td>Quantus Insights (R)</td><td>March 5, 2026</td><td>800 (LV)</td><td>± 3.4%</td><td>42%</td><td>49%</td><td>4%</td><td>6%</td></tr><tr><td>Pan Atlantic Research</td><td>February 13 – March 2, 2026</td><td>810 (LV)</td><td>± 3.7%</td><td>40%</td><td>44%</td><td>–</td><td>16%</td></tr><tr><td>University of New Hampshire</td><td>February 12–16, 2026</td><td>1,105 (LV)</td><td>± 2.9%</td><td>38%</td><td>49%</td><td>4%</td><td>9%</td></tr><tr><td>Fabrizio, Lee & Associates (R)</td><td>January 20–24, 2026</td><td>800 (LV)</td><td>± 3.5%</td><td>45%</td><td>44%</td><td>–</td><td>11%</td></tr><tr><td>Workbench Strategy (D)</td><td>December 11 – December 16, 2025</td><td>900 (LV)</td><td>±4.4%</td><td>50%</td><td>50%</td><td>–</td><td>–</td></tr><tr><td>Pan Atlantic Research</td><td>November 29 – December 7, 2025</td><td>820 (LV)</td><td>± 3.7%</td><td>42%</td><td>43%</td><td>–</td><td>15%</td></tr><tr><td>Maine People's Resource Center</td><td>October 26–29, 2025</td><td>783 (LV)</td><td>± 3.5%</td><td>41%</td><td>45%</td><td>–</td><td>14%</td></tr><tr><td>Zenith Research (D)</td><td>October 7–10, 2025</td><td>501 (LV)</td><td>± 4.4%</td><td>38%</td><td>38%</td><td>10%</td><td>15%</td></tr></tbody></table>