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

Updated October 22, 2026, 09:28 UTC

State legislatures › Idaho Senate

Idaho Senate District 35

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

<1% chance of a Democratic win · Marty Rotz Kilhefner (D), Mark Harris (R)

Idaho Senate District 35: ForecastIdaho Senate 28: chance of a Democratic win <1%; 2024 president R+52Idaho Senate 30: chance of a Democratic win <1%; 2024 president R+62Idaho Senate 31: chance of a Democratic win <1%; 2024 president R+71Idaho Senate 32: chance of a Democratic win 3%; 2024 president R+51Idaho Senate 34: chance of a Democratic win <1%; 2024 president R+67Utah Senate 2: not up in 2026 (held by republican); 2024 president R+36Wyoming Senate 14: not up in 2026 (held by republican); 2024 president R+65Wyoming Senate 16: not up in 2026 (held by republican); 2024 president R+4Wyoming Senate 17: chance of a Democratic win >99%Idaho Senate District 35: Forecast3234UT 228WY 173031WY 1435
Safe DLean DToss-upLean RSafe RHatched: not up in 2026 (shaded by holder) · dashed: other state

District 35 is safe Republican. Of its 9 neighbouring districts, 1 favours Democrats, 8 favour Republicans. 4 of them are across the state line.

StatusForecast
Chance of a Democratic win<1%
Likely margin (80% range)R+65 to R+43, middle R+54
CandidatesMarty Rotz Kilhefner (D), Mark Harris (R)
Candidate list fromofficial
Current memberMark Harris

How it has voted

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

Legislature 2022uncontested (R)
Governor 2022R+53
Legislature 2024R+55
President 2024R+51
← RepublicanDemocratic →

Who lives here

Census Bureau, American Community Survey 2019-2023.

This districtIdaho
Median household income$85,330$74,636
Bachelor's degree or more (25+)33%31%
Median age3837
White (not Hispanic)88%79%
Black0%1%
Hispanic8%13%
Asian0%1%
Born abroad4%6%
Jobs in manufacturing8%9%
Jobs in farming or mining6%4%

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.