Massachusetts — U.S. Senate
Currently held by a Democrat · incumbent running
Democrat
Ed Markey
97%
Republican
John Deaton
3%
ForecastSafe D
- Projected margin
- D+22.6
- 80% range
- D+7.9 to D+37.3
- Partisan lean
- D+28.3
- Uncertainty multiplier
- 1.93×
The 80% range comes from 200,000 simulations in which this race’s error is correlated with every other race through the national, state and demographic layers.
How the estimate is built
70%30%
Polls 70%Fundamentals 30%
- Polling average
- D+20.9
- Fundamentals
- D+42.5
- Blended
- D+23.2
- Similar-race shift
- −2.0
- Poll–fundamentals gap
- 21.6 pts
PollingDR matchup
- Polls in window
- 7
- Distinct pollsters
- 4
- Most recent
- August 12, 2026
- Democrat
- 51.4%
- Republican
- 30.5%
- Undecided / other
- 18.1%
- Spread between polls
- 1.6 pts
Fundamentals
- Partisan lean
- D+28.3
- Elasticity
- 1.10
- Incumbency
- +4.2
- Candidate experience
- 0.0
- Fundraising
- +3.8
- National environment
- D+5.3
- Expected margin
- D+44.5