U.S. Senate · All Idaho races

Idaho

Solid R

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Todd Achilles

Independent

5 in 100

chance of winning, out of 100

Jim Risch

Republican · incumbent

95 in 100

Jim Risch wins in 95 of 100 simulations.

The polling average has Jim Risch +4.2 across 1 poll; partisan lean, the national environment and incumbency point to Jim Risch +25.1. Polls get 80% of the weight 15 days out.

Where the result could land

Every simulated outcome, grouped in 2-point steps. Projected margin Risch +8.3; 80 in 100 fall between Risch +14.5 and Risch +2.1.

The candidates

Todd Achilles

Independent · American politician (born 1967)

Theodore B. "Todd" Achilles is an American politician and U.S. Army veteran. He served as a member for the 16B district of the Idaho House of Representatives from 2024 to 2025. He is the co-founder of Veterans for Idaho Voters. He is a professor of public policy at Boise State University. Wikipedia

Raised

$1.6M

Cash on hand

$369K

Through 2026-09-30

Official website ↗

Jim RischIncumbent

Republican · American lawyer and politician (born 1943)

James Elroy Risch is an American lawyer and politician who has served as the junior United States senator from Idaho since 2009. A member of the Republican Party, he served as lieutenant governor of Idaho under governors Dirk Kempthorne and Butch Otter, and briefly as governor between their terms. Wikipedia

Raised

$4.9M

Cash on hand

$2.8M

Through 2026-09-30

Official website ↗

Natalie Fleming

Independent

Matt Loesby

Libertarian

Ballot list and short bios from Wikipedia (CC BY-SA); websites from Wikidata; fundraising from the FEC (cycle-to-date, latest report).

What if this race flips? Try it in the map builder →

Polls

The polling average stands at Risch +4.3 across 1 poll testing Todd Achilles against Jim Risch.

Achilles +1.6 since Aug 7, 2026

Line: weighted average after adjustments; band: 95% range of the average; dots: individual polls after adjustments.

Pollster	Dates	Sample	Result	Adjusted	Weight
The Bullfinch Group	Aug 4–Aug 7	608 LV	Risch +4.0	Risch +4.2	0.34

Chance of winning over time

How this race’s odds have moved as polls and the national environment changed.

Achilles +4 over the past 3 months

Out of 100. Today: Achilles 5, Risch 96.

What’s driving the forecast

The model blends each estimate by how much to trust it right now. Polls get 81% of the weight, 15 days out.

Polling average (after adjustments)	Risch +4.3	±7.8 sampling range; effective 1 polls
Partisan lean (Cook PVI, 2026 lines)	R+18.0	roughly 36 points of margin vs. the nation
National environment	D+9.6	generic ballot + presidential approval
Incumbent’s track record	Achilles +5.4	In 2014 they ran 10.9 pts more Democratic than the state’s lean predicted; half carries over (max 10)
Incumbency	Risch +3.0	incumbent’s side
Fundamentals estimate	Risch +25.1	±11 typical error
Expert ratings (average)	Risch +22.0	used only in the “+ Expert ratings” version
Forecast	Risch +8.3	±5.0 standard deviation, including 2.3 for movement before Election Day

All three versions

Polls only: Todd Achilles 22 in 100 (Likely R)
Polls + fundamentals: Todd Achilles 5 in 100 (Solid R)
Polls + fundamentals + experts: Todd Achilles <1 in 100 (Solid R)

Published ratings

Other forecasters’ ratings, as listed on Wikipedia. Shown for comparison; they feed only the “+ Expert ratings” version.

Cook: Solid RDDHQ: Safe RThe Economist: Safe RSplit Ticket/FPO: Safe RFox News: Solid RInside Elections: Solid RRCP: Solid RSabato: Safe RSilver Bulletin: Solid RSplit Ticket: Safe R

County map

Counties colored by the 2024 presidential vote; on election night this switches to the live count in this race.

Color shows the 2024 presidential margin in each county. Hover or tap a county for its numbers.

2024 results: Fox News 2024 county results, compiled by Tony McGovern (github.com/tonmcg/US_County_Level_Election_Results_08-24). Not authoritative.

Rules and notes

Todd Achilles is an independent. Seats won by independents who haven’t said which party they’d caucus with are counted separately in chamber control.
Last polls close at 10 pm and 11 pm Eastern.
Last election: 62.62% R
Incumbent renominated

Senate races, closest first · this is #14 of 35