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Horizon · our Election Day forecast: polls, plus fundamentals like incumbency, fundraising and past results.

Pulse · polls only: where the races stand today, with no fundamentals and wider uncertainty.

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Massachusetts › U.S. Senate · November 3, 2026 · Updated Oct 16, 2026

U.S. Senate in Massachusetts

Markey is very likely to win: Markey wins in more than 99 of every 100 simulations.

Markey (D)
>99%
chance of winning
Deaton (R)
<1%
Average margin
D+32.5
80% of outcomes
D+25 to D+41
Partisan lean
D+28
Polls
11in our database

Markey is very likely to win: Markey wins in more than 99 of every 100 simulations.

Markey (D)
>99%
chance of winning
Deaton (R)
<1%
Average margin
D+33.7
80% of outcomes
D+25 to D+43
Partisan lean
D+28
Polls
11in our database

Range of outcomes

D+32.5R+40R+20EvenD+20D+40
D+33.7R+40R+20EvenD+20D+40

How the odds have moved

Chance of winning by forecast date.

0%25%50%75%100%AugSepOctNovNov 3Markey >99%Deaton <1%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

0%25%50%75%100%AugSepOctNovNov 3Markey >99%Deaton <1%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

The candidates

DemocraticIncumbent

Ed Markey

Incumbent U.S. senator (2013–present)

Experience
Statewide office or Congress
Raised
$5.4M
From individuals
$2.4M
Spent
$5.8M
Cash on hand
$1.3M

Money: FEC, through Aug 12, 2026.

Profile and career · Wikipedia

Republican

John Deaton

Attorney and nominee for U.S. Senate in 2024

Experience
No elected office
Raised
$1.6M
From individuals
$553.5K
Spent
$977.4K
Cash on hand
$670.7K

Money: FEC, through Sep 30, 2026.

Profile and career · Wikipedia

Party for Socialism and Liberation

Joe Tache

Organizer

Experience
No elected office
Raised
$279.5K
From individuals
$278.4K
Spent
$225.7K
Cash on hand
$53.8K

Money: FEC, through Sep 30, 2026.

Profile and career

What goes into the forecast

Every ingredient's estimate of the final margin.

National environment
D+9.5Election Day forecast; federal races run in it
← RepublicanDemocratic →Lean + environmentUsual vote, shifted by the national and state moodD+36.9Fundamentals modelAdds incumbency, past results, money andexperienceD+34.7Polls in similar placesPolling of similar races in Massachusetts andlook-alike placesD+36.8Polling average10 polls, latest Sep 22D+30.9Horizon forecastPolls + fundamentals, projected to Election DayD+32.5Pulse forecastPolls (and polling of similar places) only, todayD+33.7

Each estimate is a margin before national and statewide uncertainty is simulated. Horizon blends polls, fundamentals and a little of the similar-places estimate, weighting each by how precise it is; Pulse uses polls and similar places only.

Fundamentals inputs
Incumbency (+1 D, −1 R)1
Fundraising edge (log ratio of individual money)1.42
Elected-experience edge1
First-term incumbent0
Seat's last result vs. expectation5.13
Incumbent's last result vs. expectation5.13

Polls

R+20EvenD+20Avg. D+30.9Nov 23Nov 3
All 11 polls
PollsterDatesSampleMarkeyDeatonMarginAdjusted
MassINC Polling GroupSep 14–Sep 22800 LV5226D+26D+32.7
MassINC Polling GroupSep 14–Sep 22800 LV5428D+26D+32.7
University of New HampshireSep 17–Sep 21564 LV5330D+23D+28.0
University of New HampshireAug 20–Aug 24881 LV4930D+19D+25.3
UMass Amherst/YouGov for WCVBAug 5–Aug 12800 RV5130D+21D+26.5
University of New HampshireJun 18–Jun 23623 LV5034D+16D+20.6
Suffolk University for The Boston GlobeJun 8–Jun 12500 LV5530D+25D+28.8
University of New HampshireApr 16–Apr 20603 LV5532D+23
University of New HampshireFeb 12–Feb 16620 LV5627D+29
Cygnal for Deaton's campaignR-sponsoredJan 22–Jan 25800 LV5430D+24
Suffolk University for The Boston GlobeNov 19–Nov 23500 RV5431D+23

Adjusted: after correcting for the pollster's house effect, registered vs. likely voters, and movement in the national environment since the poll; shown for the polls carrying the most weight in today's average. Larger dots in the chart carry the most weight. Last poll: Sep 22, 2026.

The state

Lean D+28: how much more Democratic or Republican than the nation it votes for president.

Presidential vote

← RepublicanDemocratic →2016 presidentD+29.3D+27.1 vs. nation2020 presidentD+34.2D+29.7 vs. nation2024 presidentD+25.9D+27.4 vs. nation

Who lives here

Population
7,044,056
Adults with a B.A.+
47%
White, no degree
35%of adults
  • White 67%
  • Hispanic 13%
  • Black 6%
  • Asian 7%
  • Other / multiracial 7%

American Community Survey 2020–2024, aggregated from census tracts.

Past results

2024 President Vote in this state

3,377,821 two-party votes · D+25.9 · D+27.4 vs. the nation
✓ Kamala Harris (D)63.0%
Donald Trump (R)37.0%

2020

3,556,708 votes · D+33.4
✓ Edward J. Markey (D)66.3%
Kevin J. O'Conner (R)33.1%
Shiva Ayyadurai (OTH)0.6%

2020 President Vote in this state

3,549,404 two-party votes · D+34.2 · D+29.7 vs. the nation
✓ Joe Biden (D)67.1%
Donald Trump (R)32.9%

2016 President Vote in this state

3,086,089 two-party votes · D+29.3 · D+27.1 vs. the nation
✓ Hillary Clinton (D)64.7%
Donald Trump (R)35.3%

2014

2,081,894 votes · D+23.9
✓ Edward J. Markey (D)62.0%
Brian J. Herr (R)38.0%

2008

2,991,731 votes · D+36.1
✓ John F. Kerry (D)65.9%
Jeffrey K. Beatty (R)31.0%
Robert J. Underwood (L)3.1%

2002

1,975,783 votes · Uncontested by the other party
✓ John F. Kerry (D)81.3%
Michael E. Cloud (L)18.7%

Also on the ballot in Massachusetts

GovernorMaura HealeyMike Minogue>99%Dem.>99%Dem.