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

Updated October 22, 2026, 09:28 UTC

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Texas Senate District 21

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

>99% chance of a Democratic win · Julie Dahlberg (R), Judith Zaffirini (D)

Texas Senate District 21: ForecastTexas Senate 14: not up in 2026 (held by democrat); 2024 president D+48Texas Senate 18: chance of a Democratic win <1%Texas Senate 19: chance of a Democratic win 97%Texas Senate 20: not up in 2026 (held by democrat); 2024 president R+4Texas Senate 25: not up in 2026 (held by republican); 2024 president R+1Texas Senate 27: not up in 2026 (held by republican); 2024 president R+12Texas Senate 5: chance of a Democratic win 4%Texas Senate District 21: Forecast142025275181921
Safe DLean DToss-upLean RSafe RHatched: not up in 2026 (shaded by holder) · dashed: other state

District 21 is safe Democratic. Of its 7 neighbouring districts, 3 favour Democrats, 4 favour Republicans.

StatusForecast
Chance of a Democratic win>99%
Likely margin (80% range)D+20 to D+42, middle D+31
CandidatesJulie Dahlberg (R), Judith Zaffirini (D)
Candidate list fromaggregator (The Ballot Brief)
Current memberJudith Zaffirini

How it has voted

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

Legislature 2022D+26
Governor 2022D+17
← RepublicanDemocratic →

Who lives here

Census Bureau, American Community Survey 2019-2023.

This districtTexas
Median household income$67,657$76,292
Bachelor's degree or more (25+)27%33%
Median age3236
White (not Hispanic)24%40%
Black3%12%
Hispanic69%39%
Asian1%5%
Born abroad18%17%
Jobs in manufacturing6%9%
Jobs in farming or mining3%2%

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.