Resolution criteria on PolyGram: This market will resolve according to the party of the candidate who wins the IL-15 congressional district seat in the U.S. House of Representatives in the 2026 midterm elections. The midterm elections will take place on November 4, 2026. A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 House elections are conclusively called by this market's resolution sources.
PolyGram is an on-chain prediction market where you trade YES or NO outcome shares with real USDC on Polygon. For this market, buy YES if you believe the event will happen, or NO if you think it won't. Your maximum loss is your stake — winning shares pay $1.00 each at resolution. Unlike sportsbooks, there is no house edge: prices are set by supply and demand from other traders and reflect the crowd's real-time probability.
Market outcomes
| B | — | |
| Democratic Party | 7% YES | 94% NO |
| C | — | |
| Republican Party | 94% YES | 7% NO |
| Other | — | |
| D | — | |
| A | — | |
| E | — | |
Illinois's 15th congressional district will elect a representative to the U.S. House in the 2026 midterm elections on 4 November. The seat has shifted considerably over recent cycles: Republican John Shimkus held it from 1997 until his retirement in 2020, after which Democrat Mary Miller won the seat. Miller, a Trump-endorsed Republican, then flipped the district back to Republican control in 2022 with a decisive margin. The district spans central Illinois and encompasses parts of Champaign, Vermilion, and Edgar counties, reflecting a mix of rural and semi-urban constituencies.
Historical performance suggests IL-15 remains competitive but leans Republican in the current political environment. Miller's 2022 victory margin of roughly 13 percentage points indicated a rightward shift from the 2020 result, when Democrat Betsy Dirksen Londrigan lost by approximately 6 points. Comparable Midwestern districts of similar demographic composition have shown volatility between cycles, making the seat neither safely held nor clearly vulnerable at this stage.
Traders should monitor candidate announcements in the coming months, particularly whether Miller seeks re-election or whether either party fields a particularly strong challenger. Redistricting outcomes and any shifts in the district's boundaries remain relevant, though Illinois's map was finalised following the 2020 census. National political momentum heading into 2026, polling data from the district itself, and fundraising totals will provide concrete signals as the election cycle develops. The Polymarket order book will reflect evolving assessments of these factors as information accumulates.
The Speaker of the Illinois House of Representatives is seventh in the line of succession to the office of Governor of Illinois.
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.
The mechanics for trading "IL-15 House Election Winner" are the same as any other PolyGram political 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.
$22K in lifetime turnover and $39K of resting liquidity puts this market in the below the median by volume for politics contracts on PolyGram. Order-book depth is modest — expect a couple of cents of slippage on $1k+ trades.
The market has been open for 3 months — the price has had time to stabilise as new information arrived.
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.
Resolution is handled by the UMA optimistic oracle on Polygon. A proposer submits the outcome, a 2-hour dispute window opens, and if uncontested the payout is final. Contested outcomes escalate to UMA token holders.
This prediction market is scheduled to close on 3 November 2026. After the resolving event occurs, settlement typically clears within 24 hours once the UMA optimistic oracle confirms the outcome. All payouts are in USDC on the Polygon network.
To trade on this prediction market, create a free PolyGram account at polygram.ink, deposit USDC via Polygon, and place a YES or NO order on the outcome you believe in. You can learn more on our how-it-works page. Your maximum loss is limited to your stake — there is no leverage or margin.
When the outcome is determined, winning YES shares pay out $1.00 each in USDC, while losing shares pay $0. Settlement is handled by the UMA optimistic oracle on Polygon — a proposer submits the result, a two-hour dispute window opens, and if uncontested, payouts are distributed automatically. You can withdraw your winnings to any Polygon wallet.
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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