2026 midterms · data for reporters

Where Kalshi and Polymarket disagree on the 2026 election

The Democratic odds on both prediction markets for Senate control, House control and every Senate race, logged every 5 minutes (every minute on election night), 17 hours so far. Free to cite: Source: ArbTrader, arbtrader.co/election/data.

Widest gap so far: Michigan Senate, 6 points apart on Nov 1, 3:49 AM ET (Kalshi 76%, Polymarket 82%).
65%69%73%76%80%Oct 31, 7 PM ETNov 1, 11 AM ET
Senate control: Democratic odds. ■ Kalshi   ■ Polymarket
85%89%93%96%100%Oct 31, 7 PM ETNov 1, 11 AM ET
House control: Democratic odds. ■ Kalshi   ■ Polymarket

Right now

As of Nov 1, 11:41 AM ET. Gap = points between the two prices for the Democratic side.

MarketKalshiPolymarketGap
Michigan Senate77%81%4
Ohio Senate71%74%3
New Hampshire Senate93%95%2.3
Minnesota Senate91%93%2.1
Kansas Senate51%53%2
Iowa Senate44%42%2
Texas Senate69%71%2
South Carolina Senate28%26%2
Florida Senate12%10%2
Kentucky Senate4%2%1.7
Illinois Senate98%99%1.5
House control94%95%1.5
Massachusetts Senate99%100%1.2
Oklahoma Senate2%1%1.2
New Jersey Senate98%99%1.1

Widest gaps in the last 17 hours

"5+ pts" is roughly how long the two sites were at least 5 points apart.

MarketWidestWhen5+ pts
Michigan Senate6Nov 1, 3:49 AM ET (K 76%, P 82%)109 min
Minnesota Senate3.3Oct 31, 7:52 PM ET (K 91%, P 94%)–
Ohio Senate3Nov 1, 10:07 AM ET (K 71%, P 74%)–
Florida Senate3Oct 31, 11:15 PM ET (K 12%, P 9%)–
New Hampshire Senate2.3Nov 1, 11:41 AM ET (K 93%, P 95%)–
Kansas Senate2Nov 1, 1:56 AM ET (K 51%, P 53%)–
Iowa Senate2Nov 1, 12:01 AM ET (K 44%, P 42%)–
Texas Senate2Nov 1, 11:04 AM ET (K 69%, P 71%)–
South Carolina Senate2Oct 31, 9:18 PM ET (K 28%, P 26%)–
Maine Senate2Oct 31, 9:39 PM ET (K 68%, P 70%)–
Illinois Senate1.8Nov 1, 12:26 AM ET (K 98%, P 100%)–
House control1.8Oct 31, 11:15 PM ET (K 93%, P 95%)–

Download the full log (CSV)

How to read this

Prices are the cheapest offer to buy the Democratic side on each site, which works as the market's odds (62% = 62¢ for a $1 payout), before fees. They aren't the same contract: Kalshi's race markets pay on which party's candidate is sworn in and Polymarket's on the projected winner, so some gap can be the rules, not disagreement. Gaps of a few points during fast news are normal; long, wide gaps are the interesting ones.

Questions or a custom cut of the data for a story: [email protected]. Live side-by-side odds: arbtrader.co/election. ArbTrader isn't affiliated with Kalshi or Polymarket. Not financial advice.