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Will Todd Achilles (I) win the Idaho U.S. Senate election on November 3, 2026?

Resolves Yes if Todd Achilles (I) is certified as the winner of the Idaho U.S. Senate seat contested on November 3, 2026, and No otherwise. If the contest is not decided on election night — because of a runoff, a ranked-choice tabulation, or a recount — it resolves on the final certified result. Declared candidates: Todd Achilles (I); Jim Risch (R).

Forecasted on

Forecast probabilities

  • Yes: 3.5%
  • No: 96.5%

Reasoning

Todd Achilles has a 3.5% chance of winning; Jim Risch is the overwhelming favorite, with a 96.5% chance of holding the seat. The late polling offers Achilles a sliver of possibility, but it sits against Idaho’s deep Republican lean and a broader body of surveys showing Risch well ahead.

Yes — 3.5%: A narrow opening for an independent

Achilles is not a purely symbolic challenger. He has held elected office, campaigned extensively, and gained a clearer path to anti-Risch voters when Democrat David Roth withdrew and Democrats rallied behind him [a3, a4] [e3, e20]. A July poll also suggested some Republicans were open to supporting a strong independent, while an August survey briefly showed Achilles ahead—evidence that his appeal may reach beyond the Democratic base [e38] [e4].

The strongest reason not to dismiss an upset is the Achilles campaign’s late poll: it showed Risch ahead by just six points, with 8% undecided [e110]. The national mood is also favorable to Democrats, whose candidates lead the generic congressional ballot by substantial margins; dissatisfaction with President Trump could create headwinds for Republican candidates [e96, e117] [e122]. Idaho’s Proposition 1 may further energize voters opposed to the state’s abortion ban [e115]. Those factors could make the race closer than the state’s usual partisan pattern suggests.

No — 96.5%: Idaho’s gravity, reinforced by the polls

The underlying terrain is formidable for Achilles. Idaho is solidly Republican, no Democrat has won a Senate seat there in more than 50 years, and national coverage has not treated this as a competitive contest [a1, a6]. Risch is a long-serving incumbent with a prominent committee chairmanship and President Trump’s endorsement; he also has raised more than Achilles [a5, a6] [e103]. Achilles’s campaign and military background, town halls, and broader outreach give him organization, but they do not erase that structural advantage [a3, a4] [a5].

The polling evidence mostly points the same way. Risch’s campaign reported leads of 25 points and 27 points in separate surveys, and a Wall Street Journal report described a lead of about 40 points [e111] [e1] [e2]. The more favorable late poll was released by Achilles’s own campaign and still showed him losing, with little time left for a large shift [e110]. The earlier August poll putting Achilles ahead is encouraging for his supporters, but it conflicts with those later results [e4].

Why the balance favors No

The race has real features that make Achilles more plausible than a typical long-shot independent: opposition consolidation, a favorable national environment, and a late poll showing a narrower margin than other surveys. But the clearest current evidence still has Risch ahead, and the weight of polling, incumbency, and Idaho’s partisan baseline makes an upset unlikely. That combination supports Yes at 3.5% and No at 96.5%.

Update summary

A newly released Achilles-campaign poll puts Risch only six points ahead, a closer result than the previously known late polling, though it still shows Achilles trailing and is campaign-sponsored [e110] [e1]. A separate Risch-campaign poll adds little new evidence because its wide lead is consistent with earlier results [e111] [e1].

Cited evidence