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. Primary elections are scheduled to take place on June 9, 2026. Both the primary and general elections will be conducted with ranked-choice voting. The election is expected to be among the most competitive Senate races in 2026. Incumbent Republican U . senator Susan Collins is running for re-election to a sixth term and is uncontested in the primary. Graham Platner is the presumptive Democratic nominee.

Infobox

Nominee

Susan Collins (presumptive)

Party

Republican

Tables

· Republican primary › Fundraising

Candidate

Campaign finance reports as of March 31, 2026

Candidate

Campaign finance reports as of March 31, 2026

Raised

Campaign finance reports as of March 31, 2026

Spent

Campaign finance reports as of March 31, 2026

Cash on hand

Carmen Calabrese (R)

Campaign finance reports as of March 31, 2026

Carmen Calabrese (R)

Campaign finance reports as of March 31, 2026

$17,760

Campaign finance reports as of March 31, 2026

$21,260

Campaign finance reports as of March 31, 2026

Susan Collins (R)

Campaign finance reports as of March 31, 2026

Susan Collins (R)

Campaign finance reports as of March 31, 2026

$13,223,555

Campaign finance reports as of March 31, 2026

$4,517,900

Campaign finance reports as of March 31, 2026

$10,000,848

Source: Federal Election Commission

Campaign finance reports as of March 31, 2026

Source: Federal Election Commission

Campaign finance reports as of March 31, 2026
Candidate	Raised	Spent	Cash on hand
Carmen Calabrese (R)	$17,760	$21,260	$0
Susan Collins (R)	$13,223,555	$4,517,900	$10,000,848
Source: Federal Election Commission

· Republican primary › Polling

University of New Hampshire

Poll source

University of New Hampshire

Date(s) administered

February 12–16, 2026

Sample size

417 (LV)

Margin of error

± 4 %

Carmen Calabrese

Susan Collins

67%

Dan Smeriglio

Other

Undecided

25%

University of New Hampshire

Poll source

University of New Hampshire

Date(s) administered

October 16–21, 2025

Sample size

417 (LV)

Margin of error

± 4 %

Carmen Calabrese

Susan Collins

66%

Dan Smeriglio

Other

Undecided

27%

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 %	1%	67%	6%	1%	25%
University of New Hampshire	October 16–21, 2025	417 (LV)	± 4 %	1%	66%	1%	4%	27%

· Democratic primary › Fundraising

Candidate

Campaign finance reports as of March 31, 2026

Candidate

Campaign finance reports as of March 31, 2026

Raised

Campaign finance reports as of March 31, 2026

Spent

Campaign finance reports as of March 31, 2026

Cash on hand

David Costello (D)

Campaign finance reports as of March 31, 2026

David Costello (D)

Campaign finance reports as of March 31, 2026

$143,481

Campaign finance reports as of March 31, 2026

$96,333

Campaign finance reports as of March 31, 2026

$47,149

David Evans (D)

Campaign finance reports as of March 31, 2026

David Evans (D)

Campaign finance reports as of March 31, 2026

$6,437

Campaign finance reports as of March 31, 2026

$6,437

Campaign finance reports as of March 31, 2026

Tucker Favreau (D)

Campaign finance reports as of March 31, 2026

Tucker Favreau (D)

Campaign finance reports as of March 31, 2026

$13,599

Campaign finance reports as of March 31, 2026

$4,913

Campaign finance reports as of March 31, 2026

$5,170

Dan Kleban (D)

Campaign finance reports as of March 31, 2026

Dan Kleban (D)

Campaign finance reports as of March 31, 2026

$458,787

Campaign finance reports as of March 31, 2026

$458,367

Campaign finance reports as of March 31, 2026

$420

Andrea LaFlamme (D)

Campaign finance reports as of March 31, 2026

Andrea LaFlamme (D)

Campaign finance reports as of March 31, 2026

$7,740

Campaign finance reports as of March 31, 2026

$1,929

Campaign finance reports as of March 31, 2026

$5,811

Janet Mills (D)

Campaign finance reports as of March 31, 2026

Janet Mills (D)

Campaign finance reports as of March 31, 2026

$5,359,823

Campaign finance reports as of March 31, 2026

$4,285,470

Campaign finance reports as of March 31, 2026

$1,074,353

Graham Platner (D)

Campaign finance reports as of March 31, 2026

Graham Platner (D)

Campaign finance reports as of March 31, 2026

$11,956,530

Campaign finance reports as of March 31, 2026

$9,225,672

Campaign finance reports as of March 31, 2026

$2,730,858

Daira Smith-Rodriguez (D)

Campaign finance reports as of March 31, 2026

Daira Smith-Rodriguez (D)

Campaign finance reports as of March 31, 2026

$242,582

Campaign finance reports as of March 31, 2026

$242,582

Campaign finance reports as of March 31, 2026

Jordan Wood (D)

Campaign finance reports as of March 31, 2026

Jordan Wood (D)

Campaign finance reports as of March 31, 2026

$3,098,912

Campaign finance reports as of March 31, 2026

$2,178,443

Campaign finance reports as of March 31, 2026

$920,470

Source: Federal Election Commission

Campaign finance reports as of March 31, 2026

Source: Federal Election Commission

Campaign finance reports as of March 31, 2026
Candidate	Raised	Spent	Cash on hand
David Costello (D)	$143,481	$96,333	$47,149
David Evans (D)	$6,437	$6,437	$0
Tucker Favreau (D)	$13,599	$4,913	$5,170
Dan Kleban (D)	$458,787	$458,367	$420
Andrea LaFlamme (D)	$7,740	$1,929	$5,811
Janet Mills (D)	$5,359,823	$4,285,470	$1,074,353
Graham Platner (D)	$11,956,530	$9,225,672	$2,730,858
Daira Smith-Rodriguez (D)	$242,582	$242,582	$0
Jordan Wood (D)	$3,098,912	$2,178,443	$920,470
Source: Federal Election Commission

· Democratic primary › Polling

270toWin

Source of poll aggregation

270toWin

Dates administered

March 5–31, 2026

Dates updated

April 7, 2026

Janet Mills

31 %

Graham Platner

53 %

Other/Undecided

15 %

Margin

Platner +21 %

Decision Desk HQ

Source of poll aggregation

Decision Desk HQ

Dates administered

through April 9, 2026

Dates updated

April 17, 2026

Janet Mills

29 %

Graham Platner

59 %

Other/Undecided

10 %

Margin

Platner +29 %

Race to the WH

Source of poll aggregation

Race to the WH

Dates administered

February 24 – April 9, 2026

Dates updated

April 17, 2026

Janet Mills

29 %

Graham Platner

58 %

Other/Undecided

12 %

Margin

Platner +28 %

RealClearPolitics

Source of poll aggregation

RealClearPolitics

Dates administered

February 12 – March 31, 2026

Dates updated

April 7, 2026

Janet Mills

31 %

Graham Platner

53 %

Other/Undecided

14 %

Margin

Platner +22 %

Average

Source of poll aggregation

Average

Dates administered

30 %

Dates updated

56 %

Janet Mills

13 %

Graham Platner

Platner +25 %

Source of poll aggregation	Dates administered	Dates updated	Janet Mills	Graham Platner	Other/Undecided	Margin
270toWin	March 5–31, 2026	April 7, 2026	31 %	53 %	15 %	Platner +21 %
Decision Desk HQ	through April 9, 2026	April 17, 2026	29 %	59 %	10 %	Platner +29 %
Race to the WH	February 24 – April 9, 2026	April 17, 2026	29 %	58 %	12 %	Platner +28 %
RealClearPolitics	February 12 – March 31, 2026	April 7, 2026	31 %	53 %	14 %	Platner +22 %
Average			30 %	56 %	13 %	Platner +25 %

· Democratic primary › Polling

Workbench Strategy (D)

Poll source

Workbench Strategy (D)

Date(s) administered

April 6–9, 2026

Sample size

600 (LV)

Margin of error

–

David Costello

–

Janet Mills

29%

Graham Platner

64%

Jordan Wood

–

Other

–

Undecided

Maine People's Resource Center (D)

Poll source

Maine People's Resource Center (D)

Date(s) administered

March 20–31, 2026

Sample size

514 (LV)

Margin of error

–

David Costello

Janet Mills

28%

Graham Platner

61%

Jordan Wood

–

Other

–

Undecided

Emerson College

Poll source

Emerson College

Date(s) administered

March 21–23, 2026

Sample size

530 (LV)

Margin of error

± 4 %

David Costello

Janet Mills

28%

Graham Platner

55%

Jordan Wood

–

Other

Undecided

13%

Impact Research (D)

Poll source

Impact Research (D)

Date(s) administered

March 19–23, 2026

Sample size

500 (LV)

Margin of error

–

David Costello

–

Janet Mills

28%

Graham Platner

66%

Jordan Wood

–

Other

–

Undecided

Quantus Insights (R)

Poll source

Quantus Insights (R)

Date(s) administered

March 5, 2026

Sample size

450 (LV)

Margin of error

± 3 %

David Costello

–

Janet Mills

38%

Graham Platner

43%

Jordan Wood

–

Other

–

Undecided

19%

Pan Atlantic Research

Poll source

Pan Atlantic Research

Date(s) administered

February 13 – March 2, 2026

Sample size

367 (LV)

Margin of error

–

David Costello

Janet Mills

39%

Graham Platner

46%

Jordan Wood

–

Other

–

Undecided

11%

University of New Hampshire

Poll source

University of New Hampshire

Date(s) administered

February 12–16, 2026

Sample size

462 (LV)

Margin of error

± 4 %

David Costello

Janet Mills

26%

Graham Platner

64%

Jordan Wood

–

Other

Undecided

Workbench Strategy (D)

Poll source

Workbench Strategy (D)

Date(s) administered

December 11–16, 2025

Sample size

500 (LV)

Margin of error

–

David Costello

–

Janet Mills

40%

Graham Platner

55%

Jordan Wood

–

Other

–

Undecided

Pan Atlantic Research

Poll source

Pan Atlantic Research

Date(s) administered

November 29 – December 7, 2025

Sample size

318 (LV)

Margin of error

–

David Costello

Janet Mills

47%

Graham Platner

37%

Jordan Wood

–

Other

–

Undecided

14%

Z to A Research (D)

Poll source

Z to A Research (D)

Date(s) administered

November 14–18, 2025

Sample size

845 (LV)

Margin of error

± 3 %

David Costello

Janet Mills

38%

Graham Platner

58%

Jordan Wood

–

Other

Undecided

Maine People's Resource Center (D)

Poll source

Maine People's Resource Center (D)

Date(s) administered

October 26–29, 2025

Sample size

783 (V)

Margin of error

± 3 %

David Costello

–

Janet Mills

39%

Graham Platner

41%

Jordan Wood

Other

–

Undecided

14%

–

Poll source

–

Date(s) administered

47%

Sample size

53%

Margin of error

–

David Costello

–

Janet Mills

–

SoCal Strategies

Poll source

SoCal Strategies

Date(s) administered

October 21–25, 2025

Sample size

500 (LV)

Margin of error

± 4 %

David Costello

Janet Mills

41%

Graham Platner

36%

Jordan Wood

Other

–

Undecided

20%

NRSC (R)

Poll source

NRSC (R)

Date(s) administered

October 22–23, 2025

Sample size

647 (LV)

Margin of error

± 3 %

David Costello

–

Janet Mills

25%

Graham Platner

46%

Jordan Wood

Other

–

Undecided

26%

University of New Hampshire

Poll source

University of New Hampshire

Date(s) administered

October 16–21, 2025

Sample size

510 (LV)

Margin of error

± 4 %

David Costello

Janet Mills

24%

Graham Platner

58%

Jordan Wood

Other

Undecided

14%

Poll source	Date(s) administered	Sample size	Margin of error	David Costello	Janet Mills	Graham Platner	Jordan Wood	Other	Undecided
	April 30, 2026	Mills withdraws
Workbench Strategy (D)	April 6–9, 2026	600 (LV)	–	–	29%	64%	–	–	7%
Maine People's Resource Center (D)	March 20–31, 2026	514 (LV)	–	2%	28%	61%	–	–	9%
Emerson College	March 21–23, 2026	530 (LV)	± 4 %	1%	28%	55%	–	4%	13%
Impact Research (D)	March 19–23, 2026	500 (LV)	–	–	28%	66%	–	–	6%
Quantus Insights (R)	March 5, 2026	450 (LV)	± 3 %	–	38%	43%	–	–	19%
Pan Atlantic Research	February 13 – March 2, 2026	367 (LV)	–	4%	39%	46%	–	–	11%
University of New Hampshire	February 12–16, 2026	462 (LV)	± 4 %	1%	26%	64%	–	3%	6%
	January 31, 2026	Favreau withdraws
Workbench Strategy (D)	December 11–16, 2025	500 (LV)	–	–	40%	55%	–	–	5%
Pan Atlantic Research	November 29 – December 7, 2025	318 (LV)	–	1%	47%	37%	–	–	14%
Z to A Research (D)	November 14–18, 2025	845 (LV)	± 3 %	0%	38%	58%	–	2%	2%
	November 12, 2025	Wood withdraws
Maine People's Resource Center (D)	October 26–29, 2025	783 (V)	± 3 %	–	39%	41%	5%	–	14%
Maine People's Resource Center (D)	October 26–29, 2025	783 (V)	± 3 %	–	47%	53%	–	–	–
SoCal Strategies	October 21–25, 2025	500 (LV)	± 4 %	1%	41%	36%	2%	–	20%
NRSC (R)	October 22–23, 2025	647 (LV)	± 3 %	–	25%	46%	3%	–	26%
University of New Hampshire	October 16–21, 2025	510 (LV)	± 4 %	1%	24%	58%	1%	1%	14%

References

When Bruce Poliquin lost his seat
Withdrawn candidate
Key: A – all adults RV – registered voters LV – likely voters V – unclear
"Another candidate" with 1%
"Write in someone else" with 4%
Resigned as campaign political director and withdrew endorsement after controversy around old Reddit comments.
Pinny Beebe-Center, state senator from the 12th district (2022–present) Chip Curry, state senator from the 11th distric
Mana Abdi, state representative from the 95th district (2022–present) Matthew Beck, state representative from the 122nd
Calculated by taking the difference of 100% and all other candidates combined.
LaFlamme and "Someone else" with 2%
LaFlamme with 2%; "Another candidate" with 1%; Evans and Favreau with 0%
Evans and LaFlamme with 1%; Favreau with 0%
With undecided and Wood votes re-allocated based on second-choice preference
"Write in someone else" with 1%; Evans, Favreau, and LaFlamme with 0%
"Someone else" with 6%
Someone else / Third party with 3%, would not vote with 1%
"Another candidate" with 4%
"Another candidate" with 9%; "Would not vote" with 1%
"Someone else" with 8%
Someone else / Third party with 6%, would not vote with 1%