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Forecast · r64-20260730-236b8cdd42f0 · as of 2026-07-30

The Senate · Massachusetts

Projected resultModel share · middle 80% of simulations · chance to win
DEd Markey1,498,780 votes
59.7
RJohn Deatoncurated races.json precedence944,871 votes
37.6
Other67,810 votes
2.7
remainder

Projected turnout: 2,511,461 votes · model estimate, not counted votes.

Displayed shares include the model's Other-vote allowance and therefore add to 100%. Interval endpoints are the model's 10th and 90th percentiles, not a polling margin of error.

SURE 56 · moderate

How reliable is the evidence behind this race's number — not who wins. A safe seat with no polls can score low while its forecast is easy.

Effective poll evidence0.97
Race-specific error SD7.9 points
Historically calibrated 80% half-range±9.2
Model treatmentSenate exact-production calibration
Fundamentals Environment Polls Money (FEC) Roster settled

SURE v3 — historically calibrated evidence-conditioned uncertainty · generated 2026-07-27. SURE rates the EVIDENCE behind a race's number, not the outcome: a safe seat with no polls can score low while its forecast is easy. Never a second win probability. It changes only idiosyncratic uncertainty, never the center. Senate marginal intervals are historically calibrated under the stated 0-120 day assumptions; House/Governor conditioning is provisional and widen-only until chamber-specific history passes the same gates.

County by county

County view
Projected margin
R+40R+20EvenD+20D+40
Striped = seat changes partyProjected county outcome

Counties colored by the projected margin — the 2024 result shifted by the state's projected swing, summing exactly to the forecast above. Hover a county for its numbers.

CountyMarginEd MarkeyJohn DeatonTotal
MiddlesexD+37.4396,550176,261588,706
WorcesterD+7.1159,017137,289304,528
EssexD+17.3166,525116,316290,690
NorfolkD+26.0171,87899,316278,719
PlymouthD+5.8111,97499,373217,212
SuffolkD+50.0159,06351,123216,019
BristolR+2.195,834100,108201,379
HampdenD+5.877,89869,104151,081
BarnstableD+18.662,33342,284107,520
HampshireD+40.442,21917,46461,339
BerkshireD+37.433,48014,87849,700
FranklinD+35.820,3499,40830,583

All 14 counties, largest projected vote pool first. Projected: the 2024 result shifted by the state's projected swing, summing exactly to the forecast above. Model estimate, not counted votes.

State of the race

Call the Map currently has Markey ahead of Deaton by D+22.7, with a >99 in 100 chance to win. The seat is currently held by a Democrat. That result would keep the seat with Democrats. The current 5-poll average is D+20.9.

Not competitive.

CTM forecast
Solid D hold · >99 in 100
Seat
Dem.-held · projected hold
Forecast range
D+11.3 to D+34.1
Polling
D+20.9 · 5 polls
Daily forecast

How the race is moving

100%D win probability today

Since the Jul 21 edition: margin 5.5 pts toward R · win probability +1 pts D

Estimated two-party vote shareLine = estimate · tint = 80% of simulations
D 61.3%● R 38.7%
Win probabilityProbability in each tracked daily edition
D 100%● R 0%

Tracked editions only. The pale segment marks the time remaining to Election Day; it is not fabricated future data. Hover, tap, or focus a chart and use the arrow keys for each edition's exact values.

How the margin was built

Five contributions, summing to the forecast D+22.7. Every model adjustment is published here — including candidate-quality shifts. Read how the whole margin is built →

Comparable evidenceFloor 0.05 · precision discount 0.1

TWIN neighbours

TWIN means Typology-Weighted Inference from Neighbors, Call the Map’s comparable-unit matching engine for any kind of race. It borrows poll residuals only—never centers, terrain, or outcomes. Similarity is demographic and behavioural, not geographic, and each contribution decays with similarity distance. Borrowed evidence always has lower precision than a race’s own polling.

Borrowed term: ±0.000 points. This race has its own usable polling, so TWIN does not return borrowed evidence to it.

Signals at a glance

2024 presidential
D+25.3
Cook PVI
D+14.0
Historical match quality
77/100 — How closely this race matches its eight historical analogues; not a win probability.

Recent polling

University of New Hampshire2026-06-23n=623D+16×0.72
Suffolk University2026-06-12n=500D+25×0.54
University of New Hampshire2026-04-20n=603D+23×0.24
University of New Hampshire2026-02-16n=620D+29×0.09
Cygnal (R)2026-01-25n=800D+24×0.03

5 polls · weighted average D+21 · Full polling for this race →

Poll data via VoteHub, used under CC BY 4.0.

What would change this forecast

Computed from the model's own mechanics

This race is rated Solid D at D+26.6. Its win probability is separately >99%. These are the concrete, checkable events that would move that rating — computed by inverting the model's own poll blend and environment elasticity, not asserted. If one happens and the rating doesn't move, the model was wrong in public.

To Likely D

No single poll can re-rate this Likely D — the blend would need a poll at R+119, which no real poll shows.

The environment alone can't plausibly do it (it would have to reach R+22.8).

Poll and environment levers reverse the current blend (K=6) and environment sensitivity (0.6); rating lines use the same published point-margin bands as every race hero, map, and table. Win probability remains a separate quantity. Method on the methodology page. These are illustrations; they do not change the published forecast.

Money & Ads

Money in this race

Explore all spending →

Candidate filings and outside spending

FEC receipts · independent expenditures

Candidate fundraising and independent expenditures answer different questions, so they are kept separate here. Receipts are money raised by the candidate committees; the air-war bars are outside groups spending for or against a nominee.

Candidate fundraising · FEC receiptsEd Markey $4.8M vs John Deaton $1.5M

Outside spending over time

Independent expenditures reported to the FEC, by the month the money flew. Pre-primary bars can be intra-party spending, so the monthly shape is more informative than one undifferentiated total.

helps Ed Markey (D) helps John Deaton (R)
Show PAC and outside-group detail
Ed Markey$90 for · $1.5M against
ADVANCE PROGRESSagainst$1.5M
GIVEGREEN UNITED ACTIONfor$80
SIERRA CLUB INDEPENDENT ACTIONfor$10
John Deaton$0 for · $0 against

No outside spending recorded for this side yet.

Source: FEC independent-expenditure records ↗

The available FEC data here does not include candidate disbursements, cash on hand, or booked broadcast and digital reservations, so this page does not infer those measures from receipts or outside spending.

Total supporting$0
Total opposing$2.6M
FEC transactions8

Who does this money help? These are independent expenditures — spending by groups that are not the campaigns and may not coordinate with them. Each dollar is reported either supporting one candidate or opposing another, and both can help the same person, so the table below nets them out per candidate. It lists everyone with reported activity in this cycle's FEC filings — which can include primary candidates who are no longer on the ballot.

CandidateSupporting themOpposing themNet for them
Ed Markey DNominee$1.5M−$1.5M
Seth Moulton DPrimary field$1.1M−$1.1M
FEC committee activity

Direct PAC support

$535.6K · 195 transactions
  • Edward J. MarkeyNominee$491.1K
  • Seth MoultonNot on the ballot$44.5K
FEC independent expenditures

Top outside spenders

Support and opposition reported separately
Editorial context · zero model weight

Campaign videos & ads

2 campaign videos — exact reviewed channels
Campaign materialSenator Markey voted to send me and my fellow Marines to IraqSeth Moulton · Campaign video · 2026-07-23Watch on YouTube ↗
Campaign materialSeth Moulton Successfully Pushes War Powers Resolution VoteSeth Moulton · Campaign video · 2026-07-23Watch on YouTube ↗

Official FEC independent expenditures. Cycle totals may include primary spending. Direct PAC totals include governed committee contributions and in-kind contributions. Campaign-video embeds are metadata-only editorial context from exact, reviewed channels; inclusion does not establish paid placement. Outside spending and campaign videos have zero forecast weight; direct PAC activity is reporting only.

Previous results · this seat

On the same ballot in Massachusetts