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Us presidential election

Trade: Which party will win the Senate in 2026?

Opened · Settles · 62 comments

Resolution criteria on PolyGram: This market will resolve according to the party that controls the Senate following the 2026 U.S. Senate elections scheduled for November 3, 2026. Senate control is defined as having more than half of the voting Senate members, or half of the voting Senate members and the Vice Presidency. If the outcome of this election is ambiguous given the above rules, this market will remain open until the Majority Leader of the US Senate is selected following the 2026 US general election, at which point it will resolve to the party the majority leader is affiliated with at the time of their election to that position.

Real-money prediction markets aggregate live odds from thousands of traders, surfacing a sharper probability than any single forecast. Current odds favour the NO side at 49%, making this a coinflip market with 160 days to resolution, giving the order book ample time to absorb new information, backed by $430K of resting liquidity.

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.

Liquidity
$430K
Total Volume
$2.5M
24h Volume
$8K
Open Interest
$3.5M
Trade this market on PolyGram →

Market outcomes

Democratic Party 49% YES52% NO
Republican Party 52% YES49% NO
Party A
Party B
Party C
Party D
Party E
Party F

Market context

The 2026 midterm elections will determine which party controls the United States Senate for the final two years of President Biden's term. Currently trading at 48% on Polymarket's order book, the implied probability reflects substantial uncertainty about whether Republicans will retain their narrow majority or Democrats will gain the six seats required for control. Senate control hinges on outcomes in competitive races across states with varying political leanings, making this market sensitive to shifting electoral fundamentals.

Historical precedent suggests midterm elections typically favour the opposition party when an incumbent president's approval rating is below 50%. The 2022 midterms defied this pattern, with Republicans gaining only three Senate seats despite favourable conditions. The 2026 cycle will test whether that result represented a durable shift in electoral behaviour or an anomaly. Comparable cycles—particularly 1998 and 2002—show how presidential popularity, economic conditions, and candidate quality can override typical midterm dynamics, with outcomes ranging from opposition gains of two seats to losses of five.

Traders should monitor economic data releases, presidential approval trends, and candidate recruitment announcements throughout 2025 and into 2026. Recent polling from major outlets will provide early signals about competitive state races, though historical accuracy of midterm forecasts remains limited beyond six months before election day. The timing of any significant legislative achievements or crises could reshape the political environment substantially. Retirements and primary contests in key states—particularly those with retiring senators or vulnerable incumbents—will clarify the competitive landscape and likely shift market pricing materially.

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.

Settlement window & payout timing

For this market, the resolution date is 3 November 2026. A UMA proposer can submit the outcome from that moment; the two-hour dispute window closes at , and assuming no counter-claim is staked, winning USDC clears to trader balances by approximately .

If a dispute is filed inside the two-hour window, the outcome escalates to UMA token-holder voting, which extends settlement by roughly 48 hours. This particular market has no public resolution feed listed; disputes here are more likely if the underlying outcome is subject to interpretation, in which case the UMA token-vote arbitrates the wording of the original market question.

Withdrawal pace from your PolyGram balance is non-custodial and immediate — once payout clears, funds are yours to send to any Polygon wallet you control. Funds clear directly to your in-app USDC balance on Polygon. Withdrawals are non-custodial: send to any address you control, typical confirmation under 30 seconds, gas paid in USDC if you'd rather not hold MATIC.

Trading mechanics

Minimum order size on PolyGram is $1.00, with no maximum cap aside from available book depth. Orders route into Polymarket's on-chain CLOB on Polygon; the matching engine pairs YES buyers with NO buyers atomically — every executed trade is settled on-chain with no counterparty risk. For "Which party will win the Senate in 2026?", order-book behaviour for this market reflects the underlying volatility of the outcome — patient limit orders typically fill closer to mid than market orders.

The trade ticket includes a slippage box (default 2%, configurable 0.1%-10%) that caps the worst-case entry price. Your maximum loss is your stake — winning YES (or NO) shares pay $1.00 each at resolution. With this market's current book depth ($430K of resting liquidity), a $500 order should fill with single-cent slippage at the displayed mid-price.

PolyGram charges 0% house edge — no spread mark-up, no rake on winnings, no withdrawal fees beyond network gas. The platform earns exclusively from optional features (copy-trade boosts, advanced order types, the yield vault on idle USDC); the trading surface itself is at-cost.

How to trade this market step by step

The mechanics for trading "Which party will win the Senate in 2026?" 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?

$2.5M in lifetime turnover and $430K of resting liquidity puts this market in the top 2% by volume for us presidential election contracts on PolyGram. Order-book depth is exceptional — among the deepest order books in the category.

Last 24 hours alone saw $8K in turnover, consistent with the market's lifetime daily-average pace.

The market has been open for 11 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.
This market's resolution criterion
For "Which party will win the Senate in 2026?", the resolution criterion is: This market will resolve according to the party that controls the Senate following the 2026 U.S. Senate elections scheduled for November 3, 2026. Senate control is defined as having more than half of the voting Senate members, or half of th…

See the full prediction-market glossary →

Frequently asked questions

How does this market resolve?

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.

When does this market close?

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.

How can I trade on "Which party will win the Senate in 2026?"?

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.

What happens when the market resolves?

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.

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. For "Which party will win the Senate in 2026?", the considerations above apply directly — Trade size should reflect the binary nature of the payoff: even a 70% probability event resolves NO 30% of the time, so any single position can lose 100% of staked capital.

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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