Senate control 2026

Kalshi vs Polymarket: Will Democrats win the U.S. Senate in 2026

Last checked 2026-09-04 21:13 UTC. Prices move constantly; the rules comparison is the durable part.

Not verified as the same bet. The venues' published terms differ in ways that could settle differently.

SETTLEMENT_POLICY_MISMATCH — both venues publish settlement policy, but the published texts diverge
SETTLEMENT_GUARANTEE_UNKNOWN — the venue does not publish enough settlement policy to prove what happens in every branch (missing data, cancellation, revision)
SETTLEMENT_TIMING_ASYMMETRIC — one venue may settle well before the other, so a paired position is not truly locked until both have settled

In plain words. Where they differ: both venues publish settlement policy, but the published texts diverge; the venue does not publish enough settlement policy to prove what happens in every branch (missing data, cancellation, revision); one venue may settle well before the other, so a paired position is not truly locked until both have settled. Kalshi's fine print: the rules never say what happens to open positions if the event is canceled, voided, or never takes place; the rules never say whether a later revision of the underlying number changes the outcome; the rules publish no terminal branch for the case where the deciding number is never released or the criterion never fires; no settlement terms could be read from the published text in a form that determines an outcome. In an ordinary outcome both contracts pay the same. The difference shows up only in the unusual case those gaps describe — a delayed release, a canceled event, a revised number — which is exactly when a paired position stops being one bet.

The Polymarket leg here is the global venue, which US accounts cannot trade; it is shown for the rules comparison only.

Venue	Contract	YES price	Taker fee at that price
Kalshi	Will Democrats win the U.S. Senate in 2026? kalshi:CONTROLS-2026-D Open on Kalshi	48¢	2.0¢
Polymarket (global)	Will the Democratic Party control the Senate after the 2026 Midterm elections? polymarket_global:562793 Open on Polymarket (global)	52¢	set per market

YES price is the best ask at the last check. Fees use each venue's published taker formula at that price — see the fee calculator for any price.

Capital lock-up: about 149.7 days until the later of the two contracts settles. early settlement possible on kalshi

Kalshi fine-print grade: D (40/100)
−20 MISSING_CANCELLATION_POLICY: the rules never say what happens to open positions if the event is canceled, voided, or never takes place
−15 MISSING_REVISION_POLICY: the rules never say whether a later revision of the underlying number changes the outcome
−15 NO_EXPLICIT_EXCEPTION_FALLBACK: the rules publish no terminal branch for the case where the deciding number is never released or the criterion never fires
−10 UNPARSED_SETTLEMENT_POLICY: no settlement terms could be read from the published text in a form that determines an outcome

What Kalshi publishes

If the Democratic Party has won control of the U.S. Senate in 2026, then the market resolves to Yes. This market may be determined early based on a consensus of media calls projecting control of the U.S. Senate. See full rules for details. Otherwise, victory will be determined by the party identification of the President pro tempore of the Senate on February 1, 2027.

What Polymarket publishes

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 convenes after the specified election is affiliated. The following rules govern the counting of seats for determining which party wins control of the chamber. All regular and special Senate elections that determine representation in the upcoming 120th Congress and are scheduled to take place in November 2026 as of October 31, 2026 are included. Runoffs for qualifying elections will determine attribution of the relevant seat, even if they take place after November 2026. Vacant seats for which no election or special election to fill the seat is scheduled to take place in November 2026 as of October 31, 2026 will be treated as held by the party affiliation of the most recent member to hold that seat. For seats contested in the specified election, seats are attributed to the party under which the member was elected. If a member-elect changes party affiliation, or vacates their seat, betwe