About 2 in 3▲ Up 2 pts this week
Kalshi shows a last trade; Polymarket shows a price to buy. $100 on Polymarket at the ask pays $153 if correct, before fees.
Democrats are strong favorites for the House. The Senate is closer, and the 51st seat runs through Ohio.
About 2 in 3▲ Up 2 pts this week
Kalshi shows a last trade; Polymarket shows a price to buy. $100 on Polymarket at the ask pays $153 if correct, before fees.
About 19 in 20Unchanged this week (Kalshi)
Prices to buy now. $100 on Kalshi at the ask pays $108 if correct, before fees.
Change in percentage points over 7 days, from daily closing prices to the latest observation (Oct 4, 10:02 AM ET).
Chance the Democrat wins each race, from Kalshi, closest races first.
Kalshi prices to buy; a stale quote shows its last price instead. “Buy GOP” buys No on the Democratic contract, except in Nebraska, where an independent is running. Tap a price to open that race’s market.
| Race | Dem chance | 7 days | Buy Dem | Buy GOP | Sources |
|---|---|---|---|---|---|
| Iowa Stale quoteTurek (D) vs. Hinson (R) | 44% At last trade, $100 returns $229 | +1 pts | Dem43.5¢ | GOPStale | Sources & contracts› |
| Maine Stale quoteJackson (D) vs. Collins (R) | 59% At last trade, $100 returns $170 | −1 pts | Dem58.5¢ | GOPStale | Sources & contracts› |
| Ohio 51st seatBrown (D) vs. Husted (R) | 63% At last trade, $100 returns $160 | +5 pts | Dem62.5¢ | GOPStale | Sources & contracts› |
| TexasTalarico (D) vs. Paxton (R) | 64% $100 on GOP at the ask pays $270 | +5 pts | Dem65¢ | GOP37¢ | Sources & contracts› |
| Kansas | 36% $100 on Dem at the ask pays $277 | +6 pts | Dem36¢ | GOP65¢ | Sources & contracts› |
| MichiganEl-Sayed (D) vs. Rogers (R) | 72% $100 on GOP at the ask pays $344 | – | Dem72¢ | GOP29¢ | Sources & contracts› |
| Alaska Stale quotePeltola (D) vs. Sullivan (R) | 73% At last trade, $100 returns $136 | +3 pts | Dem73¢ | GOPStale | Sources & contracts› |
| New HampshirePappas (D) | 86% $100 on GOP at the ask pays $666 | +1 pts | Dem87¢ | GOP15¢ | Sources & contracts› |
| Minnesota Stale quote | 87% At last trade, $100 returns $115 | −2 pts | Dem86.5¢ | GOPStale | Sources & contracts› |
| South Carolina Stale quote | 14% At last trade, $100 returns $740 | +1 pts | Dem13.5¢ | GOPStale | Sources & contracts› |
| FloridaSpecial election | 12% $100 on Dem at the ask pays $769 | +2 pts | Dem13¢ | GOP89¢ | Sources & contracts› |
| Mississippi Stale quote | 10% At last trade, $100 returns $985 | – | Dem10.2¢ | GOPStale | Sources & contracts› |
| Arkansas Stale quote | 7% At last trade, $100 returns $1,418 | – | Dem7¢ | GOPStale | Sources & contracts› |
| Louisiana Stale quote | 7% At last trade, $100 returns $1,449 | −3 pts | Dem6.9¢ | GOPStale | Sources & contracts› |
| Tennessee | 7% $100 on Dem at the ask pays $1,234 | +5 pts | Dem8.1¢ | GOP94.6¢ | Sources & contracts› |
| North Carolina Stale quoteCooper (D) | 95% At last trade, $100 returns $104 | +2 pts | Dem95.3¢ | GOPStale | Sources & contracts› |
| Georgia Stale quoteOssoff (D) | 96% At last trade, $100 returns $104 | +2 pts | Dem95.8¢ | GOPStale | Sources & contracts› |
| Kentucky Stale quote | 4% At last trade, $100 returns $2,469 | −1 pts | Dem4¢ | GOPStale | Sources & contracts› |
| Alabama Stale quote | 3% At last trade, $100 returns $3,773 | – | Dem2.6¢ | GOPStale | Sources & contracts› |
| Wyoming Stale quote | 3% At last trade, $100 returns $4,000 | – | Dem2.5¢ | GOPStale | Sources & contracts› |
| West Virginia Stale quote | 2% At last trade, $100 returns $4,081 | – | Dem2.5¢ | GOPStale | Sources & contracts› |
| Oklahoma Stale quote | 2% At last trade, $100 returns $4,347 | +1 pts | Dem2.3¢ | GOPStale | Sources & contracts› |
| Illinois Stale quote | 98% At last trade, $100 returns $102 | – | Dem97.8¢ | GOPStale | Sources & contracts› |
| New Mexico Stale quote | 98% At last trade, $100 returns $101 | +1 pts | Dem98.1¢ | GOPStale | Sources & contracts› |
| Virginia Stale quote | 98% At last trade, $100 returns $101 | – | Dem98.4¢ | GOPStale | Sources & contracts› |
| Massachusetts Stale quote | 99% At last trade, $100 returns $101 | – | Dem98.5¢ | GOPStale | Sources & contracts› |
| Oregon Stale quote | 99% At last trade, $100 returns $101 | +1 pts | Dem98.6¢ | GOPStale | Sources & contracts› |
| Delaware Stale quote | 99% At last trade, $100 returns $101 | – | Dem98.6¢ | GOPStale | Sources & contracts› |
| New Jersey Stale quote | 99% At last trade, $100 returns $101 | +1 pts | Dem98.6¢ | GOPStale | Sources & contracts› |
| Colorado Stale quote | 99% At last trade, $100 returns $101 | – | Dem98.7¢ | GOPStale | Sources & contracts› |
| Rhode Island Stale quote | >99% At last trade, $100 returns $100 | – | Dem99.1¢ | GOPStale | Sources & contracts› |
| Montana Stale quote | <1% At last trade, $100 returns $11,111 | −1 pts | Dem0.90¢ | GOPStale | Sources & contracts› |
| Nebraska IndependentOsborn (I) vs. Ricketts (R) · Kalshi asks if a Democrat wins | <1% At last trade, $100 returns $12,500 | +1 pts | Dem0.80¢ | GOPSee note | Sources & contracts› |
| Idaho Stale quote | <1% At last trade, $100 returns $20,000 | – | Dem0.50¢ | GOPStale | Sources & contracts› |
| South Dakota Stale quote | <1% At last trade, $100 returns $33,333 | – | Dem0.30¢ | GOPStale | Sources & contracts› |
Source: Kalshi / Polymarket via DeFi Rate, observed between Oct 4, 8:18 AM and 10:01 AM ET. Some quotes are stale: they weren’t observed recently and may have moved, so they show their last price and aren’t offered as a price to buy. Each race’s sources show when.
Every venue we track, the range they span, and how our figure sits inside it. Open any source to see the contract, bid and ask, and quote age.
| Source | Price | In our figure? |
|---|---|---|
| RTWH model model | 68.9% | No · forecast model |
| 64.5% | Yes · constructed | |
| 64.5% | Yes | |
| PM US | 63.7% | No · editor-observed Sep 22 |
| Gemini | 60.0% | No · editor-observed Sep 22 |
| 64.5% | Average of the two “Yes” rows |
The gap has held for several days, which usually points to different traders rather than stale data.
Long shots are often priced higher on one venue. The 2-cent gap is about 20% of the price.
Races tend to move together, so the gap may be smaller than it looks. Treat it as a question to investigate, not a trade.
Models and markets use different inputs. A model above the market means it’s more bullish on Democrats than traders are.
Each venue’s price for the market you pick, what your order would pay, and the estimated fee.
| Venue | Price | 24h traded | Est. fee | Payout if correct | Trade |
|---|---|---|---|---|---|
| Kalshi | Stale quote: not observed recently, so it isn’t offered as a price to buy. Its last price and age are in the source record. | ||||
| PolymarketSenate-control contract · quote 2 min old | 65¢Price to buy | $53K | n/a | $153before fees | Polymarket65¢ |
| Polymarket US | 63.7¢ observed on polymarket.us by an editor on Sep 22; not averaged. | ||||
| Gemini | 60¢ observed on Gemini by an editor on Sep 22; not averaged. | ||||
| OG | Senate control isn't in our feed yet. | ||||
Kalshi has no single Senate-control contract; its price combines two contracts that settle in Feb 2027, so it isn’t marked as comparable with Polymarket.
“Price to buy” is the venue’s current ask; “last trade” is the most recent trade and may not be available now. We don’t yet measure how many contracts are available at a price, so large orders may fill higher. Est. fee uses Kalshi’s published taker-fee formula, per contract in a bundle; other venues’ fees aren’t in our feed. DeFi Rate may earn a commission when you open an account through these links. 18+ (21+ in some states).
Each market asks a yes-or-no question, such as “Will Democrats control the Senate?” A contract pays $1 if the answer is yes and $0 if it’s no, so its price works as a probability: 64¢ means traders collectively put the chance at about 64%.
Take the Texas Senate race. If James Talarico trades at 58¢, 100 contracts cost $58. If he wins, they pay $100, a $42 profit before fees. If he loses, they’re worth nothing. You don’t have to hold until Election Day: if the price rises to 75¢ and someone is buying, you can sell early and keep the difference.
A price isn’t a poll. A candidate at 60¢ doesn’t have 60% of the vote; traders think they have about a 60% chance of winning.
Kalshi, Polymarket US and Gemini are federally regulated US exchanges that offer these markets. Polymarket’s international exchange lists many of the same questions, but it isn’t available to US residents.
Nothing requires two exchanges to agree. Each has its own traders and order book, and some questions are built differently. Kalshi, for example, has no single Senate-control contract; its figure comes from adding two balance-of-power contracts. The source comparison shows every venue’s price next to ours, and labels which comparisons are like-for-like.
A gap isn’t free money. The displayed prices may not be available in size, fees reduce the difference, and the contracts may settle on slightly different terms.
The market title isn’t the contract. Each one names its resolution source and says what happens after a recount, a runoff, a tie or a delayed certification. A network projection doesn’t settle anything. Every source record on this page links to the contract so you can read its rules before you trade.
In a thin market, the quoted price may only be available for a few contracts. Larger orders can fill at worse prices.
Kalshi, Gemini Titan and QCX LLC (which operates Polymarket US) are designated contract markets registered with the CFTC. The CFTC disapproved Kalshi’s congressional-control contracts in 2023; a federal court vacated that decision in 2024, and the appeal was dismissed in 2025. The CFTC chair has since warned that attempts to move political markets artificially could bring manipulation cases, and the Senate has barred senators and staff from trading these markets. Availability can still vary by platform and state, so check before you fund an account.
Live odds for Maine's 2026 Senate election.
Live odds on which party will control the House after the 2026 midterms.
Live odds for Texas's 2026 Senate election.
Live odds for the four House and Senate control combinations.
Live odds for Michigan's 2026 Senate election.
The two headline figures average Kalshi and Polymarket bid/ask midpoints for the same outcome. Kalshi has no single Senate-control contract, so its Senate price is built from its own two balance-of-power contracts and labeled “constructed.” State races use Kalshi alone. Open any Sources link for the exact contracts. Full methodology →
Pat Evans has covered complex industries for nearly two decades, including sports betting, sports business and, at iGaming Business, prediction markets, before joining DeFi Rate in 2026.
Cheryle Shepstone is DeFi Rate’s Director of Content and Strategy and oversees its prediction-market research, platform reviews and editorial methodology.