15% — 2026 midterm election odds
Kalshi 15% · 11 contracts · $6K volume · medium confidence
Updated 2026-09-22 16:16:47 UTC

Why this matters:
Prediction markets currently indicate a moderate outlook for the 2026 midterms, assigning an 84% probability to a scenario where Democrats hold at least 218 House seats and 49 Senate seats. A more aggressive outcome requiring 235 House seats and 51 Senate seats is viewed as significantly less likely at a 48% probability. Furthermore, there is a 38% market-implied chance that an independent or third-party candidate will win a seat in either chamber of Congress.

Key factors:
- 84% probability for 218 House/49 Senate seats
- 48% probability for 235 House/51 Senate seats
- 38% chance of third-party victory
- 63% chance of Democratic sweep in GA, MI, NC, and ME

Contracts:
- Will Michigan have the smallest margin of victory in 2026 United States Senate elections?: Michigan — 9¢ Kalshi $1K (weight 25%)
- Will Maine have the smallest margin of victory in 2026 United States Senate elections?: Maine — 8¢ Kalshi $1K (weight 18%)
- Will New Hampshire have the smallest margin of victory in 2026 United States Senate elections?: New Hampshire — 4¢ Kalshi $857 (weight 15%)
- Will Democrats win the 2026 senate elections in Georgia, Michigan, North Carolina, AND Maine?: Yes — 58¢ Kalshi $636 (weight 11%)
- Will Alaska have the smallest margin of victory in 2026 United States Senate elections?: Alaska — 8¢ Kalshi $524 (weight 9%)
- Will Texas have the smallest margin of victory in 2026 United States Senate elections?: Texas — 15¢ Kalshi $523 (weight 9%)
- Will The winning team of the 2026 Pro football Championship visit The White House before Dec 31, 2026?: Yes — 26¢ Kalshi $269 (weight 5%)
- Will Iowa have the smallest margin of victory in 2026 United States Senate elections?: Iowa — 12¢ Kalshi $246 (weight 4%)
- ... and 3 more

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## Methodology

SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours.

## SF Signal

- SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration.
- No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only.

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*Last verified: 2026-09-22T15:20:52.022Z*

By SimpleFunctions — https://simplefunctions.dev/

Cite as: "15% per prediction markets (SimpleFunctions, September 2026)"
Canonical: https://simplefunctions.dev/answer/election-2026
Full data: https://simplefunctions.dev/api/public/query?q=2026%20midterm%20election%20odds
Provider: SimpleFunctions — https://simplefunctions.dev