TOTAL VOLUME:
$154.8b
24H VOL:
$277,138,640
24H TRANSACTIONS:
2,984,640,614
OPEN INTEREST:
$1,905,404,943
412,077
Markets across
39,838
events
MATCHED EVENTS:
4,526
PLATFORM COVERAGE:
5
Polymarket:
37%
VS.
Kalshi:
63%
Closed: Oct 5, 11:09 AM EST
Kalshi
Description
This group forecasts which political party will hold the most seats in the Brazilian Senate following the 2026 election. The election will determine two-thirds of the Senate's 81 seats, but all seats are considered for determining the majority. In the event of a tie, the party appearing first alphabetically will be considered the winner.
PredictionHero - Resolution Divergence Alerts (RDA)
Divergence Detected
Issue: Kalshi markets focus on specific, named parties, while Polymarket includes generic 'Party X' options, creating a difference in market scope and potential for resolution outcomes.Hero tip: Prioritize trading on Kalshi markets for established Brazilian parties, as Polymarket’s inclusion of generic 'Party X' options introduces significant uncertainty.Critical divergence points:
- Polymarket: Resolves based on the number of seats held by the *named* party, including generic 'Party X' options, and excludes coalition effects. Key Quote: "This market will resolve based solely on the number of seats held by the named party…not by any federation or coalition it may be a part of."
- Kalshi: Resolves if a *specific, named* party holds the most seats. Key Quote: "If PL holds the most total seats…then the market resolves to Yes."
Polymarket
The next federal Senate election is scheduled to take place in Brazil on October 4, 2026, in which two-thirds of the Senate’s 81 seats will be contested. This market will resolve according to the political party that holds the greatest number of seats in the next Brazilian Senate as a result of the next Brazilian Senate election. All seats, not only the ones contested in the next Brazilian Senate election, will be considered. In the event of a tie between multiple parties for the most seats held, this market will resolve in favor of the party whose listed abbreviation appears first in alphabetical order. This market's resolution will be based solely on the number of seats held by the named party in the Brazilian Senate as a result of the next Brazilian Senate election, not by any federation or coalition it may be a part of. If the result of this election isn't known definitively by June 30, 2027, 11:59 PM ET, the market will resolve to "Other". This market will resolve based on the result of the election, as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the Brazilian government, specifically the Superior Electoral Court (Tribunal Superior Eleitoral, TSE) (e.g., www.tse.jus.br/eleicoes/resultados-eleicoes) or the Brazilian Senate (https://www25.senado.leg.br/web/senadores/em-exercicio/-/e/por-partido).
Kalshi
The party holding the most total Senate seats after the 2026 election wins, determined by total seat count including seats not contested. A seat is won when the candidate is declared elected by the electoral authority and either the challenge period has expired, legal challenges are resolved, or the member has taken their seat. Party affiliation is based on the party under which the candidate was elected, regardless of later changes. In case of ties for the top rank, all tied parties resolve to Yes with values split proportionally. If a ranking is skipped due to ties (e.g., two parties tie for first, next is third), markets for the skipped rank resolve to No.
Frequently asked questions
Differences in prices between Polymarket and Kalshi can arise from several factors. Polymarket and Kalshi can show different implied probabilities for the same outcome because of liquidity, fee structure, participant mix, and how each venue defines the contract. Each platform has its own user base, trading dynamics, and fee structure, which can influence price discovery. Furthermore, differing liquidity levels on each venue can create temporary discrepancies. Market makers may also employ different strategies on each platform, leading to variations in the odds. While both markets track the same underlying event—the Brazil Senate election—these platform-specific factors contribute to the observed price differences.