On the eve of Brazil's October 25 runoff, prediction markets placed Flávio Bolsonaro as a heavy favorite, priced around 80% on both Polymarket and Kalshi. Luiz Inácio Lula da Silva won instead, re-elected with 64,256,232 votes and 51.79% of valid ballots, according to the Tribunal Superior Eleitoral (TSE). For Brazil 2026 prediction markets, election night became a near-laboratory test: the platforms called the race wrong with high confidence, then recognized Lula's comeback before the official count did.
Our reporting draws on the TSE note published at 00:18 on October 26, the Polymarket contract page, and the Rio Times' minute-by-minute reconstruction, which the outlet states is produced by an automated editorial system. Polymarket and Kalshi posts on X could not be opened with our tools and are reported as flagged by our newsroom. We found no corroboration for a Kalshi pre-vote price of 75%, which circulated in some reconstructions.
