Will the Democratic Party control the Senate after the 2026 Midterm elections?

Crossbook compares what two exchanges, Polymarket and Kalshi, charge for the same event, and publishes a permanent scored record of its own forecasts under published rules.

Both venues are priced below, side by side.

Informational only. Not trading or investment advice. Prices may be delayed or inaccurate, and a difference between venues can be an artifact — how this is measured.

Trading0.0pt midpoint gapContract settles 4 Nov 2026Last checked 29 Oct 2026, 19:25 UTC

Bid/ask midpoint · retrieved 2026-10-29T19:25:26.934Z. Venue quote-update time is unavailable. Readings can be asynchronous.

67.5%bid 67.0% / ask 68.0%24h volume $235K · liquidity $4.9Mas of 29 Oct, 19:25 UTCView on Polymarket

Bid/ask midpoint · retrieved 2026-10-29T19:25:30.451Z. Venue quote-update time is unavailable. Readings can be asynchronous.

67.5%bid 67.0% / ask 68.0%24h volume $356Kas of 29 Oct, 19:25 UTCView the event containing this market on Kalshi

How each venue defines this

Each exchange's own settlement text, quoted as written. Where they differ, the difference is usually why the prices do.

These two contracts name settlement dates about 3 months apart. Read both terms below for why: a later date can mean a different condition, a longer deadline or an administrative delay, and only the terms say which.

Settles Nov 4, 26

This market will resolve according to the party that wins control of the United States Senate in the 2026 United States midterm election. A party wins control of the United States Senate if it wins a majority of the chamber’s voting seats. If no party wins a majority of voting seats, the party that wins control of the chamber is the party that wins half of the voting seats and holds the Vice Presidency. If the outcome remains ambiguous after applying the above criteria, the chamber will be deemed controlled by the party with which the first selected President Pro Tempore of the Congress that…

Settles Feb 1, 27

If the Democratic Party has won control of the U.S. Senate in 2026, then the market resolves to Yes.

Settlement basis

Equivalent settlement terms · reviewed

Reviewed as equivalent: the clause from each venue that decides the outcome is quoted below, with the reviewer's reasoning and the date.

“A party wins control of the United States Senate if it wins a majority of the chamber's voting seats. If no party wins a majority of voting seats, the party that wins control of the chamber is the party that wins half of the voting seats and holds the Vice Presidency.”

“If the Democratic Party has won control of the U.S. Senate in 2026, then the market resolves to Yes. [...] victory will be determined by the party identification of the President pro tempore of the Senate on February 1, 2027.”

Same event. Polymarket counts seats as elected, with the Vice President breaking a 50-50 tie; Kalshi reads the party of the President pro tempore on 1 February 2027. Those give the same answer unless a senator changes party or caucus between the election and February, which Polymarket ignores and Kalshi would reflect. Judged immaterial to price.

Reviewed Oct 5, 26 under rules v1.3.

Confirmed as the same question: Will the Democratic Party control the Senate after the 2026 Midterm elections?

Price, last 60 days

Crossbook forecast

No public Crossbook forecast on this market yet. Every call that is made is timestamped and scored on the public record, win or lose.

Context

Polymarket and Kalshi agree on this one. Both price it near 67.5%, so there is no cross venue disagreement to trade and no basis to speak of.

Volume over the last 24 hours is heavy, at about $355,530 on the busier venue. It closes in 5 days. Prices this close to resolution move on news rather than on reassessment.

Related markets

Crossbook publishes every forecast it makes, timestamped before the answer is known and scored against the market afterwards. See the public record and the rules it is held to.