Massachusetts · 2026 forecast · Updated Oct 16, 2026
Who will control the Massachusetts State Senate?
All 40 seats are on the ballot. 21 seats make a majority. 27 make the two-thirds supermajority that can override a veto. November candidates are not yet compiled for 1 race; they are forecast for the seat's current party against a generic challenger.
1 of 40 races has no compiled candidate list yet. Those seats are forecast for their current party against a generic challenger, marked TBD below.
Democrats are very likely to control the Massachusetts State Senate (>99%).
- Avg. D seats
- 35.480% range 35–36
- Avg. R seats
- 4.680% range 4–5
- Now
- 35 D · 5 R40 up this year
Democratic supermajority now (35 of 40 seats; 27 needed for two-thirds): >99% chance it holds · <1% chance it's broken.
35 D nowMarks: two-thirds supermajority for each party5 R now
Democrats are very likely to control the Massachusetts State Senate (>99%).
- Avg. D seats
- 35.180% range 34–36
- Avg. R seats
- 4.980% range 4–6
- Now
- 35 D · 5 R40 up this year
Democratic supermajority now (35 of 40 seats; 27 needed for two-thirds): >99% chance it holds · <1% chance it's broken.
35 D nowMarks: two-thirds supermajority for each party5 R now
- Solid D
- Likely D
- Lean D
- Toss-up
- Lean R
- Likely R
- Solid R
Race ratings
All 40 races, grouped by the leader's chance of winning.
No seat is projected to change parties. 1 more is a toss-up that could change parties (flip risk).
1 seat projected to flip: 1 R→D. 1 more is a toss-up that could change parties (flip risk).
Solid D34
- First Essex
- First Middlesex
- Norfolk-Worcester-Middlesex
- Plymouth and Barnstable
- Second Bristol and Plymouth
- Second Essex and Middlesex
Show 28 more
- Berkshire-Hampden-Franklin-Hampshire
- Bristol and Norfolk
- Cape and Islands
- Fifth Middlesex
- First Suffolk
- First Worcester
- Fourth Middlesex
- Hampden
- Hampden and Hampshire
- Hampden-Hampshire-Worcester
- Hampshire-Franklin-Worcester
- Middlesex and Norfolk
- Middlesex and Suffolk
- Middlesex and Worcester
- Norfolk and Middlesex
- Norfolk and Plymouth
- Norfolk and Suffolk
- Norfolk-Plymouth-Bristol
- Second Essex
- Second Middlesex
- Second Plymouth and Norfolk
- Second Suffolk
- Second Worcester
- Suffolk and Middlesex
- Third Essex
- Third Middlesex
- Third Suffolk
- Worcester and Middlesex
Likely D1
Lean D0
Toss-up1
Lean R0
Likely R0
Solid D32
- Berkshire-Hampden-Franklin-Hampshire
- First Essex
- First Middlesex
- Hampshire-Franklin-Worcester
- Norfolk-Worcester-Middlesex
- Second Essex and Middlesex
Show 26 more
- Bristol and Norfolk
- Cape and Islands
- Fifth Middlesex
- First Suffolk
- First Worcester
- Fourth Middlesex
- Hampden
- Hampden and Hampshire
- Hampden-Hampshire-Worcester
- Middlesex and Norfolk
- Middlesex and Suffolk
- Middlesex and Worcester
- Norfolk and Middlesex
- Norfolk and Plymouth
- Norfolk and Suffolk
- Norfolk-Plymouth-Bristol
- Second Essex
- Second Middlesex
- Second Plymouth and Norfolk
- Second Suffolk
- Second Worcester
- Suffolk and Middlesex
- Third Essex
- Third Middlesex
- Third Suffolk
- Worcester and Middlesex
Lean D1
Toss-up1
Lean R0
Likely R0
Columns follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. The square shows who holds the seat now (■ Democrats, ■ Republicans). flip: projected to change parties, in the color of the party favored to gain it. risk: a toss-up (40–60%) that could change parties. Underlined: two candidates of one party in November. Faded: no major-party opponent. Dotted: no candidate list yet; forecast for the seat's party against a generic challenger.
The map
Each district colored by the leader's chance of winning. Hover for details; click for the race.
Massachusetts
Boston
- Solid D
- Likely D
- Lean D
- Toss-up
- Lean R
- Likely R
- Solid R
- Projected flip (stripes: party holding it now)
Seats to watch
The closest races (Lean or Toss-up, Horizon), and the seats most likely to change parties.
Most likely to flip
How the odds have moved
Chance of winning control, by forecast date.
Updated nightly. Each day is the current model run on the polls that had ended by then (how).
Updated nightly. Each day is the current model run on the polls that had ended by then (how).
Every outcome we simulated
Democratic seats across 40,000 simulations. Darker bars: the middle 80%.
Every race
40 races, 29 without a contest between the major parties.
| District | Candidates | Chance of winning (D · R) | Avg. margin | Rating | Lean | Polls |
|---|---|---|---|---|---|---|
| Berkshire-Hampden-Franklin-Hampshire | ● Paul MarkINC● Gabriel Greenspan | D+40.3D+37.3 | D+36 | — | ||
| Bristol and Norfolk | ● Paul FeeneyINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+18 | — | |
| Cape and Islands | ● Julian CyrINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+29 | — | |
| Fifth Middlesex | ● Kate Lipper-Garabedian● No Republican | Democrat unopposedDemocrat unopposed | — | D+34 | — | |
| First Bristol and PlymouthFlip risk | ● Michael RodriguesINC● Gabriel "Boomer" Amaral | D+13.9D+2.0 | R+4 | — | ||
| First Essex | ● Pavel PayanoINC● Fraylin S. Angelina | D+29.1D+21.1 | D+15 | — | ||
| First Essex and Middlesex | ● No Democrat● Bruce TarrINC | Republican unopposedRepublican unopposed | — | D+24 | — | |
| First Middlesex | ● Vanna HowardINC● Sam Meas | D+23.0D+21.1 | D+14 | — | ||
| First Plymouth and Norfolk | ● No Democrat● Patrick O'ConnorINC | Republican unopposedRepublican unopposed | — | D+21 | — | |
| First SuffolkD vs D | ● Nick CollinsINC● No Republican | Democrats only in NovemberDemocrats only in November | — | D+53 | — | |
| First Worcester | ● Robyn KennedyINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+32 | — | |
| Fourth Middlesex | ● Cindy FriedmanINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+35 | — | |
| Hampden | ● Adam GomezINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+34 | — | |
| Hampden and Hampshire | ● John VelisINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+11 | — | |
| Hampden-Hampshire-Worcester | ● Jacob OliveiraINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+10 | — | |
| Hampshire-Franklin-WorcesterTBD | ● No candidate● No candidate | D+44.3D+46.7 | D+45 | — | ||
| Middlesex and Norfolk | ● Karen SpilkaINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+43 | — | |
| Middlesex and Suffolk | ● Sal DiDomenicoINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+61 | — | |
| Middlesex and Worcester | ● Jamie EldridgeINC● Tim Shea | D+51.1D+49.6 | D+43 | — | ||
| Norfolk and Middlesex | ● Cynthia Stone CreemINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+65 | — | |
| Norfolk and Plymouth | ● John F. KeenanINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+17 | — | |
| Norfolk and Suffolk | ● Persis S. Yu● No Republican | Democrat unopposedDemocrat unopposed | — | D+38 | — | |
| Norfolk-Plymouth-Bristol | ● William DriscollINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+23 | — | |
| Norfolk-Worcester-Middlesex | ● Becca RauschINC● Charles Francis Bailey, III | D+32.8D+31.7 | D+26 | — | ||
| Plymouth and Barnstable | ● Dylan FernandesINC● Kari MacRae | D+19.1D+15.6 | D+12 | — | ||
| Second Bristol and Plymouth | ● Mark MontignyINC● Robert McConnell | D+19.5D+13.4 | D+6 | — | ||
| Second Essex | ● Joan LovelyINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+26 | — | |
| Second Essex and Middlesex | ● Barry FinegoldINC● Ted Semesnyei | D+31.5D+22.8 | D+16 | — | ||
| Second Middlesex | ● Erika Uyterhoeven● No Republican | Democrat unopposedDemocrat unopposed | — | D+65 | — | |
| Second Plymouth and Norfolk | ● Michael BradyINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+26 | — | |
| Second Suffolk | ● Liz MirandaINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+79 | — | |
| Second Worcester | ● Michael O. MooreINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+23 | — | |
| Suffolk and MiddlesexD vs D | ● William BrownsbergerINC● No Republican | Democrats only in NovemberDemocrats only in November | — | D+66 | — | |
| Third Bristol and Plymouth | ● No Democrat● Kelly DoonerINC | Republican unopposedRepublican unopposed | — | R+2 | — | |
| Third Essex | ● Brendan CrightonINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+22 | — | |
| Third Middlesex | ● Michael J. BarrettINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+45 | — | |
| Third Suffolk | ● Lydia EdwardsINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+38 | — | |
| Worcester and Hampden | ● No Democrat● Ryan FattmanINC | Republican unopposedRepublican unopposed | — | R+3 | — | |
| Worcester and HampshireFlip riskD flip | ● Shannon Teabo● Peter DurantINC | D+0.4D+6.7 | D+2 | — | ||
| Worcester and Middlesex | ● John CroninINC● No Republican | Democrat unopposedDemocrat unopposed | — | D+18 | — |
Lean: how much more Democratic (D+) or Republican (R+) the place voted for president than the nation (2024 weighted 75%, 2020 25%). Ratings follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. INC = incumbent running. D flip / R flip: another party is favored (60% or more) over the party holding the seat now (hover for the chance it changes parties); Flip risk: the seat is a toss-up (40–60%). Badges mark election rules (hover or long-press for details): RCV = ranked-choice voting; Top two / Top four = the leading primary finishers advance; All-party = every candidate on one November ballot; TBD = no candidate list yet, forecast for the seat's party against a generic challenger.