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

Updated October 22, 2026, 09:28 UTC

State legislatures › Missouri House

Missouri House District 66

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

>99% chance of a Democratic win · Laura Mitchell-Riley (R), Marlene Terry (D)

Missouri House District 66: ForecastIllinois House 111: chance of a Democratic win 2%; 2024 president R+13Missouri House 65: chance of a Democratic win 5%; 2024 president R+18Missouri House 67: chance of a Democratic win >99%; 2024 president D+71Missouri House 73: chance of a Democratic win >99%; 2024 president D+62Missouri House 76: chance of a Democratic win >99%; 2024 president D+80Missouri House 85: chance of a Democratic win >99%; 2024 president D+85Missouri House District 66: Forecast85737667IL 1116566
Safe DLean DToss-upLean RSafe RHatched: not up in 2026 (shaded by holder) · dashed: other state

District 66 is safe Democratic. Of its 6 neighbouring districts, 4 favour Democrats, 2 favour Republicans. 1 of them is across the state line.

StatusForecast
Chance of a Democratic win>99%
Likely margin (80% range)D+43 to D+89, middle D+66
CandidatesLaura Mitchell-Riley (R), Marlene Terry (D)
Candidate list fromofficial
Current memberMarlene Terry

How it has voted

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

Legislature 2022uncontested (D)
Legislature 2024uncontested (D)
President 2024D+75
← RepublicanDemocratic →

Who lives here

Census Bureau, American Community Survey 2019-2023.

This districtMissouri
Median household income$46,810$68,920
Bachelor's degree or more (25+)15%32%
Median age3639
White (not Hispanic)13%77%
Black83%11%
Hispanic1%5%
Asian0%2%
Born abroad1%4%
Jobs in manufacturing8%11%
Jobs in farming or mining0%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.