Election forecasts you can inspect.Tested models, shown with their sources and their uncertainty.

Updated October 22, 2026, 09:28 UTC

State legislatures › Massachusetts House

Massachusetts House District 8th Hampden

2026 forecast · Updated October 22, 2026, 09:28 UTC

Decided: only a Democrat is running · Shirley B. Arriaga (D)

Massachusetts House District 8th Hampden: Decided: only a Democrat is runningMassachusetts House 2nd Hampshire: chance of a Democratic win >99%; 2024 president D+35Massachusetts House 5th Hampden: chance of a Democratic win >99%; 2024 president D+29Massachusetts House 6th Hampden: chance of a Democratic win >99%; 2024 president evenMassachusetts House 7th Hampden: chance of a Democratic win >99%; 2024 president D+13Massachusetts House 9th Hampden: chance of a Democratic win >99%; 2024 president D+29Massachusetts House District 8th Hampden: Decided: only a Democrat is running5th Hampden6th Hampden2nd Hampshire7th Hampden8th Hampden
Safe DLean DToss-upLean RSafe RHatched: not up in 2026 (shaded by holder) · dashed: other state

District 8th Hampden is safe Democratic. Of its 5 neighbouring districts, 5 favour Democrats.

StatusDecided: only a Democrat is running
CandidatesShirley B. Arriaga (D)
Candidate list fromofficial
Current memberShirley Arriaga

How it has voted

On its current lines. Legislative contests and the top-of-ticket vote inside the district.

Legislature 2024uncontested (D)
President 2024D+5
← RepublicanDemocratic →

Who lives here

Census Bureau, American Community Survey 2019-2023.

This districtMassachusetts
Median household income$67,007$101,341
Bachelor's degree or more (25+)23%47%
Median age4340
White (not Hispanic)68%68%
Black4%7%
Hispanic23%13%
Asian2%7%
Born abroad9%18%
Jobs in manufacturing13%9%
Jobs in farming or mining1%0%

Initial version. This model was tested on every state legislative election from 1994 to 2024 before publication, forecasting each as if it had not happened. It beat the simple rule “the party that holds the seat keeps it”, and its chamber seat counts were off by 2.9 seats on average (target: under 3). Districts with no two-party race last time are read from their own presidential vote, a change tested in advance that cut their average error from 17 to 13 points. It missed one of its five accuracy targets: in 2024, the calmest year on record, its ranges were wider than they needed to be (92% of results fell inside its 80% ranges; target: at most 88%). Treat the ranges as cautious. The full test record and code.