Idaho's entrenched Republican electoral dominance, reinforced by the party's consistent hold on federal offices and a 36-point Trump margin in 2024, anchors trader consensus behind incumbent Jim Risch at over 95 percent implied probability. Risch secured the nomination with more than two-thirds of the Republican primary vote in May and holds double-digit leads in August polls against independent Todd Achilles. The July withdrawal of Democrat David Roth, who had won his party's primary, consolidated opposition behind the weaker Achilles challenge and removed any path for a competitive general election contest. Historical base rates for Senate races in similarly Republican states further support the market's assessment. Late developments such as a major scandal or health event involving Risch represent the primary realistic scenarios that could narrow the gap before November.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated$32,162 Vol.
$32,162 Vol.

Republican
96%

Democrat
3%
$32,162 Vol.
$32,162 Vol.

Republican
96%

Democrat
3%
A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.
Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Market Opened: Oct 13, 2025, 5:35 PM ET
Resolver
0x2F5e3684c...A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.
Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Resolver
0x2F5e3684c...Idaho's entrenched Republican electoral dominance, reinforced by the party's consistent hold on federal offices and a 36-point Trump margin in 2024, anchors trader consensus behind incumbent Jim Risch at over 95 percent implied probability. Risch secured the nomination with more than two-thirds of the Republican primary vote in May and holds double-digit leads in August polls against independent Todd Achilles. The July withdrawal of Democrat David Roth, who had won his party's primary, consolidated opposition behind the weaker Achilles challenge and removed any path for a competitive general election contest. Historical base rates for Senate races in similarly Republican states further support the market's assessment. Late developments such as a major scandal or health event involving Risch represent the primary realistic scenarios that could narrow the gap before November.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated


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