Brazil Electoral Forecast · Runoff
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Published on 24 October 2026
Forecast sealed before Brazil's runoff of 25 October 2026: the Presidency and the six governorships decided in the runoff. It continues the 23 September edition. Information cut-off: 24 October (01:35 UTC).
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Forecast sealed before the event
Central runoff estimate: Flávio Bolsonaro 51.8% of the valid vote and Lula 48.2% (80% band: 49.5%–54.1% for Flávio); Flávio wins the Presidency in 84% of the modelled distribution. Governorships: the first-round leader keeps the lead in five of the six states; in Tocantins the order flips.
Official result
Lula won with 51.79% of the valid vote against 48.21% for Flávio Bolsonaro, a 3.58-point margin (64.26 against 59.83 million votes). We gave Flávio 51.8% and an 84% probability of winning: we missed the winner and the magnitude, as Flávio's vote fell below the 80% band (49.5-54.1%). As we declared before the vote, with a Lula win we finish behind all three external benchmarks (average of 16 polls, 51.0% for Flávio; Datafolha, 50.0%; prediction markets, around 77%), which also had Flávio ahead or tied, but by less. In the governorships we called the winner in 5 of the 6 states (we missed Rio Grande do Norte, won by Cadu of the PT with 50.77%), and four of those five winners landed inside their band (in Tocantins, Vicentinho exceeded the band with 64.52%). Turnout: 80.78%. Source: Superior Electoral Court (TSE).
Direction: MissMagnitude: Miss
Independent verification
This document was timestamped before the event it forecasts — sealed 1 day before the event. The proof does not depend on Oliveira Vantage: anyone can check it without asking us for anything.
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078ddc6b 097d8932 e171edb0 30225700 e3a24107 1a235b48 b8754fcd 7bf05199
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Seal date: 24 October 2026 · event: 25 October 2026
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