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

Updated October 22, 2026, 09:28 UTC

State legislatures › Missouri Senate

Missouri Senate District 3

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

Not up in 2026 (held by Republican)

Missouri Senate District 3: Not up in 2026 (held by Republican)Illinois Senate 58: not up in 2026 (held by republican); 2024 president R+36Missouri Senate 16: chance of a Democratic win <1%Missouri Senate 22: chance of a Democratic win <1%Missouri Senate 26: chance of a Democratic win <1%Missouri Senate 27: not up in 2026 (held by republican); 2024 president R+56Missouri Senate District 3: Not up in 2026 (held by Republican)22261627IL 583
Safe DLean DToss-upLean RSafe RHatched: not up in 2026 (shaded by holder) · dashed: other state

District 3 is not up in 2026 (held by a Republican). Of its 5 neighbouring districts, 5 favour Republicans. 1 of them is across the state line.

StatusNot up in 2026 (held by Republican)
Current memberMike Henderson

How it has voted

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

Legislature 2024R+52
President 2024R+43
← RepublicanDemocratic →

Who lives here

Census Bureau, American Community Survey 2019-2023.

This districtMissouri
Median household income$60,298$68,920
Bachelor's degree or more (25+)16%32%
Median age4139
White (not Hispanic)91%77%
Black2%11%
Hispanic2%5%
Asian0%2%
Born abroad1%4%
Jobs in manufacturing14%11%
Jobs in farming or mining2%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.