How a 2026 Midterm Election Contract Settles
Before a single vote is counted, an election contract has already decided which result counts and who is allowed to declare it.
Published 2026-10-08 · Data as of 2026-10-08 · Market & data intelligence · Educational, not advice.
An election contract is a document written before the vote that says exactly which result settles it and who declares it. Kalshi points at official certified results from named source agencies, with certified beating preliminary and a one-year clock. Polymarket routes the same question through the UMA oracle, a two-hour challenge window, and a staked dispute vote.
A prediction market is an exchange where you take a position against another person, not against a house. Every YES contract has a counterparty holding NO; the venue matches the two, takes a fee, and never takes the other side itself. The price is just where the most recent buyer and seller agreed, and it moves continuously until the outcome is known.
For a temperature reading or an inflation print, settling that is clean. An election is harder, because an election does not produce one official number at one moment. Results trickle in, get called, get revised, and only later become final. So the contract has to say, in advance, exactly which result counts and who is allowed to declare it. That document, not the price, is where the real work hides.
What a midterm contract is written against
Start with the event. USA.gov says the next midterm elections will be in November 2026, when one-third of the Senate and every seat in the House of Representatives is up for election. That is a lot of separate questions, and each one needs its own settlement rule.
On Kalshi, that rule lives in the contract's terms. Its election contract terms template defines the underlying as the official results of the election as certified by designated source agencies. In other words, the contract does not settle on a network projection or a candidate's speech. It settles on an official, certified result.
The template also names who those source agencies are: the relevant state Secretary of State or chief election officer, and the Federal Election Commission for federal campaign matters. That matters because elections in the United States are administered state by state. Pinning settlement to a named official removes the argument about whose version of the result the contract is talking about.
Certified beats the call on the night
Election night is loud and provisional. The contract is built to ignore that noise. Under the same Kalshi template, final certified results take precedence over preliminary results when the outcome is determined. A race that looks settled at midnight can tighten as late ballots are counted, and the contract is written to wait for the official number rather than the early one.
Waiting has a limit. The template sets the latest expiration date of the contract at one year after the election. Certification normally arrives within weeks, but that one-year backstop exists because recounts, legal challenges, and runoffs can stretch the timeline. The contract gives the official process room to finish without hanging open forever.
None of this is hidden. Kalshi's help center says the information used to determine an outcome, and the source of that information, are included in each contract's own terms and conditions. The takeaway for anyone reading one of these markets is simple: the terms document is the product. Read it before you read the price.
Polymarket asks the same question a different way
A contract on the same race can settle through completely different machinery depending on the venue. Polymarket says its markets are resolved by the UMA Optimistic Oracle, a smart-contract based oracle. Rather than a named election official being written into the contract, an outcome is proposed on-chain and assumed correct unless someone challenges it.
That assumption has a window. Polymarket says once an outcome is proposed for a market, the market enters a challenge period of two hours. If nobody disputes the proposal in that time, it stands. If someone does, the question escalates. Per UMA's documentation, a disputed resolution goes to UMA's Data Verification Mechanism, where holders of staked UMA vote, and the dispute resolves only when a minimum 65 percent majority backs a single outcome.
So the two venues answer the same real-world question with different authorities. One points at a government certification and a named officer. The other points at an economic vote of token-holders with a supermajority threshold. Same election, same candidates, two different definitions of what counts as the truth and who gets to assert it.
Why the plumbing is the whole story
Comparing those two structures is not a pick and it is not a price call. It is reading the fine print that decides when your position pays and what it waits on. A contract tied to state certification behaves differently in a slow recount than one tied to a two-hour on-chain window and a dispute vote, even when the underlying race is identical.
Delta Arc's Prediction Markets product puts Kalshi and Polymarket in one place, which makes it easier to see that the same event can be framed two ways at once. As November 2026 approaches, the contracts worth understanding first are not the ones with the sharpest price. They are the ones whose settlement language you can actually read to the end.
Sources: USA.gov, Midterm elections; Kalshi election contract terms template; Kalshi Help Center, Market Outcomes; Polymarket Help Center, How Are Prediction Markets Resolved; UMA docs, How does UMA work.
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