With just 11 days until the November 3, 2026 midterms, prediction markets are telling a sharper story than most polling aggregators. As of October 23, traders on Kalshi and Polymarket price Democratic Senate control at 44%, Democratic House control at 63%, and the probability of a divided Congress at 51%. Volume across political contracts has surged roughly 38% week-over-week, and the Senate control contract alone has traded more than $18 million in notional over the last seven days.
This is the midterm market, as the crowd sees it right now.
Senate Control: A 44% Shot at Flipping
Republicans entered 2026 holding the Senate 53-47. The map favored them on paper, but a series of candidate quality issues and a soft economy have pushed the generic ballot four points in the Democrats’ direction since August. Prediction markets have moved with the data.
Here is where the key Senate toss-ups price heading into the final stretch:
| State | Incumbent / Party | Dem Win Probability | Rep Win Probability |
|---|---|---|---|
| North Carolina | Open (R) | 58% | 42% |
| Maine | Collins (R) | 47% | 53% |
| Ohio | Moreno (R) | 41% | 59% |
| Iowa | Ernst (R) | 36% | 64% |
| Georgia | Ossoff (D) | 62% | 38% |
| Michigan | Open (D) | 66% | 34% |
North Carolina is the single most-watched contract on the board. The open seat left by Thom Tillis’s retirement has drawn more than $4.2 million in Kalshi volume this week alone, and the Democratic candidate has traded between 54% and 61% all month. The crowd thinks it flips.
Maine is the race that keeps the Senate map alive for Democrats. Susan Collins at 53% is her lowest implied win probability in any cycle since 2008. If she drops below 50% in the final week, expect the Senate control contract to pop above 50% for Democrats.
House Control: Markets Lean Blue
The House is where prediction markets diverge most from the political press. Democrats need a net gain of just four seats, and traders put their chances at 63%, up from 54% at the start of October. Three forces are driving the move:
- Generic ballot drift. The RealClearPolitics generic ballot sits at D+4.1, the widest Democratic lead since July 2022.
- Retirement wave. Twelve Republican House members have announced retirements since August, including four in Biden-won 2024 districts.
- Economic sentiment. The Michigan consumer sentiment index fell to 61.4 in October, a nine-month low. Midterm markets historically track consumer sentiment closely.
The battleground district contracts tell the same story. Of the 29 districts Kalshi and Polymarket both offer, Democrats are favored in 18, Republicans in 7, with 4 priced as true coin flips. If those probabilities hold through election night, the expected Democratic seat gain is roughly plus-nine, well clear of the four they need.
Governor Races: The Underpriced Market
Governor races get a fraction of the volume of federal contracts but often resolve with the biggest surprises. Four races are drawing meaningful money this week:
- Georgia: Open seat (Kemp term-limited). Democrat at 51%, Republican at 49%. True toss-up.
- Michigan: Open seat (Whitmer term-limited). Democrat at 57%, Republican at 43%.
- Ohio: Republican incumbent at 68%. The one race on this list where the market is confident.
- Pennsylvania: Democrat Shapiro re-elect at 74%. Priced as a near lock.
The Georgia contract is the sleeper. It has the thinnest liquidity of the four and the widest bid-ask spread, which usually means a late-breaking move in either direction can push the probability 8 to 10 points in a single trading session. If you follow one gubernatorial contract into election week, that is the one.
What the Combined Markets Imply
Pulling the Senate, House, and governor contracts together produces a probability-weighted outcome that looks very different from the “Republican red wave” narrative that dominated spring 2026 commentary:
- Divided Congress (D House, R Senate): 51%
- Full Democratic sweep (D House, D Senate): 28%
- Status quo (R House, R Senate): 16%
- R House, D Senate: 5%
The headline: markets price a 79% chance Democrats take at least one chamber, and a 72% chance the Senate stays Republican. That combination, divided government with Democratic House leverage, is the single most likely outcome of this election, as the crowd sees it today.
Where to Trade These Markets
Both major US-regulated prediction markets offer the full menu of 2026 midterm contracts, with slightly different liquidity profiles. Kalshi has the deepest Senate control and House control contracts, with tight spreads and reliable fills on size. Polymarket runs larger volume on individual race contracts and governor markets, and often prices the long-tail outcomes a few points off Kalshi, creating arbitrage windows for traders who watch both.
For a side-by-side look at platform fees, deposit methods, and election market coverage, see our ranking of the best prediction markets.
Eleven days to go. The crowd thinks it already knows. We will find out on November 3.