Primary
Primary election: Tuesday, September 1, 2026
Full calendar and every race: Massachusetts primary guide
Race Overview
General Election Polling Trend
PollingSource average — trailing average of all polls from the last 90 days.
Candidates
General Election Polling Average
Average reflects all polls from the last 90 days; table shows the most recent 30 days or the newest 3 polls, whichever is more — subscribe for the full history. How accurate is each pollster? →
| Pollster | Date | Sample | MoE | Dem | Rep |
|---|---|---|---|---|---|
| UNH | 2026-06-23 | 633 LV | ±3.70 | Moulton 50.00% | Deaton 30.00% |
| University of New Hampshire | 2026-06-23 | 623 LV | ±3.80 | Ed Markey 50.00% | John Deaton 34.00% |
| University of New Hampshire | 2026-06-12 | 500 LV | ±4.40 | Ed Markey 55.00% | John Deaton 30.00% |
Questions About This Race
Who is winning the 2026 Massachusetts Senate race?
Seth Moulton leads John Deaton 52.8% to 30% in the PollingSource polling average — a D+22.8 margin based on 5 polls from the last 90 days.
Is the 2026 Massachusetts Senate race competitive?
No — the PollingSource polling average rates it Safe D for Democrats.
What does the latest poll of the 2026 Massachusetts Senate race say?
The most recent public poll, from UNH (completed June 23, 2026), found Moulton (D) at 50% and Deaton (R) at 30%.
When is the 2026 Massachusetts Senate race decided?
Election Day is Tuesday, November 3, 2026.
How is the PollingSource average calculated?
The PollingSource average is the unweighted mean of every scientific public poll of the race from the last 90 days — we do not exclude pollsters. Each race page lists the individual polls behind the average with pollster, field dates, sample size, and margin of error. Full details: pollingsource.com/methodology.
Race Notes
Long-tenured Senator
Independent Expenditures Updated 4 hours ago
Top Spenders
- ADVANCE PROGRESS $1,482,275
- COMMONWEALTH TOGETHER PAC $1,148,680
- GIVEGREEN UNITED ACTION $80
- SIERRA CLUB INDEPENDENT ACTION $10
Full outside-spending research — every committee, every race →