Trade: Idaho Senate Election Winner

Market context

The 2026 United States Senate election in Idaho will determine which candidate fills the seat currently held by Republican Mike Crapo, who is not seeking re-election. The race will take place on 3 November 2026, with any runoff occurring thereafter. The market's 93% implied probability for a winner being determined reflects the expectation that a candidate will emerge victorious through either the general election or subsequent runoff procedures, as specified in Idaho electoral law.

Idaho has voted Republican in statewide Senate races consistently since 1980, with the last Democratic Senate winner being Frank Church in 1974. The state's Republican lean has strengthened considerably in recent decades—the 2022 Senate election saw Republican Mike Crapo win with 71% of the vote. This historical context suggests the primary determinant of the general election outcome will likely be the Republican primary contest, where candidate selection typically predicts the November result. The 93% probability reflects high confidence that the election machinery will function and produce a definitive winner rather than a prediction about which party's nominee will prevail.

Key catalysts include the formal announcement of candidates from both parties, expected throughout 2025 and early 2026. The Republican primary will be particularly consequential given the state's electoral history. Traders should monitor any unexpected developments affecting candidate viability, changes to Idaho's electoral procedures, or shifts in voter registration patterns. The settlement window closes on 3 November 2026, coinciding with election day, though any runoff results would determine final resolution.

How this market resolves

Resolution is handled by the UMA optimistic oracle on Polygon. A proposer submits the outcome, a two-hour dispute window opens, and if no one stakes a counter-claim the payout is final. Contested outcomes escalate to UMA token-holder voting. Payouts clear in USDC to the winning side.

How to trade this market step by step

The mechanics for trading "Idaho Senate Election Winner" are the same as any other PolyGram event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.

1. Sign in on polygram.ink with your email — no full KYC under $1,500 lifetime trading volume.
2. Deposit USDC on Polygon (lowest fees, ~$0.01 per transaction) or Ethereum. Funds credit after 12 confirmations.
3. Pick a side. Buy YES if you believe the event will happen; buy NO if you think it won't. The current YES price reflects the market's collective probability.
4. Size your position. If you stake 100 USDC at 50% YES, you'll receive shares that pay $200 if YES resolves true — a 100% gross return. If NO resolves, your shares are worth $0.
5. Set risk controls (optional). Stop-loss, take-profit, and limit-order types all supported. Use the trade ticket's slippage box to cap your maximum entry price.
6. Wait for resolution. When the event resolves on-chain via the UMA optimistic oracle, the winning side settles to 100¢ automatically and USDC hits your balance within seconds. Withdrawable to any wallet you control.

How active is this market?

$15K in lifetime turnover and $11K of resting liquidity puts this market in the below the median by volume for midterms contracts on PolyGram. Order-book depth is modest — expect a couple of cents of slippage on $1k+ trades.

The market has been open for 7 months — long enough that the order book is mature and price is well-anchored to fundamentals.

Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.

Key terms

YES / NO share

A binary outcome token that pays $1.00 if the underlying claim resolves true (YES) or false (NO), and $0 otherwise. The market price between 0¢ and 100¢ is the implied probability.

CLOB

Central limit order book. The matching engine that pairs YES buyers with NO buyers (effectively the same trade). Polymarket's CLOB on Polygon executes trades on-chain via the conditional-tokens framework.

Liquidity

USDC capital sitting in resting limit orders inside the order book. Deeper liquidity means smaller slippage on large trades and a tighter bid-ask spread.

UMA optimistic oracle

The on-chain dispute system that settles each Polymarket market. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution.

Slippage

The difference between the displayed mid-price and your fill price. Affects market orders most; limit orders avoid slippage but may take time to fill.

Conditional token

ERC-1155 outcome share issued by Gnosis Conditional Tokens on Polygon. The token type that resolves to $1.00 or $0.00 at settlement.

See the full prediction-market glossary →

Frequently asked questions

Risk and regulatory note

Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.

Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.

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