# Brazil 2026 presidential election: what September polling says about a Lula win Polymarket asks whether Luiz Inacio Lula da Silva wins the 2026 Brazilian presidential election on 4 October, second round included. The September Quaest polling collected here runs against the proposition: it puts Flavio Bolsonaro on 42% against Lula in a simulated runoff, a one-point lead inside a two-point margin of error, and records rejection rates of 56% for Bolsonaro and 55% for Lula. Separately, 50% disapprove of the Lula government against 44% who approve. This is one pollster's September readings, not a forecast, and it says nothing about who will win. - Canonical page: https://market-claims.com/briefs/brazil-presidential-2026-lula - Category: politics - Evidence collected: 22 September 2026 - Research dated: 22 September 2026 - Published: 24 September 2026 - Market: Polymarket, https://polymarket.com/event/brazil-presidential-election#0xdf8e2dc5860027decbe6164555c3c1c9645c3bd33e16b9dc57ca87125047d4a8 - Venue YES price: 40.5c at 22 September 2026 - Market closes: 4 October 2026 Research only. Not financial advice. No trades are placed. The price is the venue's own market price at the snapshot time, shown as context only. It is not an estimate by MarketClaims. **This is an older research snapshot. It may miss subsequent developments.** ## The question, as the venue words it Will Luiz Inácio Lula da Silva win the 2026 Brazilian presidential election? ## How this market settles Resolves to the listed candidate who wins the 4 October 2026 election, including any second round. Resolution follows a consensus of credible reporting; where that is ambiguous, the official results of the Superior Electoral Court (TSE) govern. If no result is known by 30 June 2027 the market resolves to 'Other'. ## Evidence you can inspect _These labels describe how a claim relates to the question. They are not recommendations or independent votes._ ### Evidence supporting YES (0 claims) _No claims in this category. Absence here is a coverage limit, not a finding._ ### Evidence challenging YES (8 claims) - "Brazilian President and re-election candidate Luiz Inácio Lula da Silva and challenger Flávio Bolsonaro are in a technical tie less than two weeks before the elections, according to a poll published on Monday" [infobae](https://www.infobae.com/america/agencias/2026/09/21/empate-tecnico-entre-lula-y-flavio-bolsonaro-a-dos-semanas-de-los-comicios-segun-encuesta/), published 21 September 2026 - "A Quaest poll released on Monday, September 21, shows candidate Flávio Bolsonaro (PL) numerically ahead of opponent Luiz Inácio Lula da Silva (PT) in a simulated second-round presidential election" [Terra](https://www.terra.com.br/noticias/eleicoes/pesquisas/quaest-flavio-bolsonaro-e-lula-voltam-a-empatar-tecnicamente-no-2-turno,b62ba63d17f7788f6c2f59a74c84e886bwf0080n.html), published 21 September 2026 - "President Luiz Inácio Lula da Silva's campaign intends to focus more on issues prioritized by the population, such as the economy, food prices, health, and security, due to Flávio Bolsonaro's advance in polls" [G1](https://g1.globo.com/politica/eleicoes/2026/noticia/2026/09/22/lula-flavio-estrategias-reta-final-campanha.ghtml), published 22 September 2026 - "In the previous poll, conducted on September 14, Flávio Bolsonaro had 42% and Luiz Inácio Lula da Silva had 40%" [Terra](https://www.terra.com.br/noticias/eleicoes/pesquisas/quaest-flavio-bolsonaro-e-lula-voltam-a-empatar-tecnicamente-no-2-turno,b62ba63d17f7788f6c2f59a74c84e886bwf0080n.html), published 21 September 2026 - "In the simulated second round, Flávio Bolsonaro has 42% of the vote, while Luiz Inácio Lula da Silva has 41%" [Terra](https://www.terra.com.br/noticias/eleicoes/pesquisas/quaest-flavio-bolsonaro-e-lula-voltam-a-empatar-tecnicamente-no-2-turno,b62ba63d17f7788f6c2f59a74c84e886bwf0080n.html), published 21 September 2026 - "The poll has a margin of error of 2 percentage points, meaning Flávio Bolsonaro and Luiz Inácio Lula da Silva are in a technical tie" [Terra](https://www.terra.com.br/noticias/eleicoes/pesquisas/quaest-flavio-bolsonaro-e-lula-voltam-a-empatar-tecnicamente-no-2-turno,b62ba63d17f7788f6c2f59a74c84e886bwf0080n.html), published 21 September 2026 - "Quaest: rejeição a Flávio Bolsonaro é de 56% e a Lula, de 55% | G1" [G1](https://g1.globo.com/politica/eleicoes/2026/pesquisa-eleitoral/noticia/2026/09/21/quaest-rejeicao-21-setembro.ghtml), published 21 September 2026 - "Quaest: 50% desaprovam governo Lula e 44% aprovam | G1" [G1](https://g1.globo.com/politica/eleicoes/2026/pesquisa-eleitoral/noticia/2026/09/21/quaest-aprova-desaprova-governo-21-setembro.ghtml), published 21 September 2026 ### Context (0 claims) _No claims in this category. Absence here is a coverage limit, not a finding._ ## What this brief cannot settle Every finding here traces to a single pollster, Quaest, across two September waves; no other polling firm appeared in the retrieved evidence, so this is one house's view rather than a polling average. Four further claims citing gvwire.com were removed because that site blocked automated retrieval and the citation could not be checked. The market end date of 4 October does not accommodate a runoff that could run into late October or November, and the report flags that mismatch as a resolution risk, along with the undefined meaning of 'consensus of credible reporting' and of an 'Other' resolution. - The end date listed is October 4, 2026, but the election may require a second round (potentially late October/November 2026), creating a mismatch between the end date and actual resolution timing. - Resolution defaults to 'Other' if results are unknown by June 30, 2027, but it is unclear whether 'Other' constitutes a NO resolution or a separate outcome. - 'Consensus of credible reporting' is subjective and undefined — no specific outlets or threshold number of sources are specified. - Timezone not specified for the October 4, 2026 end date, potentially creating ambiguity around exact cutoff. ## Publication history - Published 24 September 2026; research dated 22 September 2026. ## Since the previous brief This is the first published brief for this event. No comparison is available. --- The same research can be run on any Polymarket or Kalshi market at https://market-claims.com.