Marcelo Castro (MDB) holds a modest lead in trader pricing for first place in the Piauí Senate contest, reflecting his status as an incumbent seeking a second term and consistent top positioning in mid-2026 surveys from firms including Amostragem, AtlasIntel, and Vetor. Ciro Nogueira (PP), the other incumbent running for a third term, trails despite name recognition, weighed down by the highest recorded rejection levels among major contenders. Júlio César (PSD) remains competitive as a federal deputy entering the race. President Lula’s September 10 endorsement of Castro and Júlio César during a Piauí event, coupled with indirect criticism of Nogueira, has reinforced the government-aligned candidates’ positioning ahead of the October 4 vote. With roughly 20 registered candidates, elevated undecided shares in earlier polling, and two seats at stake, the market continues to price a narrow contest where late campaign momentum or turnout shifts among key voter blocs could alter the order.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedMarcelo Castro 53%
Ciro Nogueira 30%
Julio Cesar 16.0%
Alexandre Mariano <1%
$39,672 Vol.
$39,672 Vol.

Marcelo Castro
53%

Ciro Nogueira
30%

Julio Cesar
11%

Alexandre Mariano
<1%

Antônio Barros
<1%

Antônio José Lira
<1%

Cloves José
<1%

Danniel Rocha
<1%

Dionisio Carvalho
<1%

Francinaldo Leão
<1%

Irmão Evandro Marques
<1%

Jardenya Bezerra
<1%

Jorge Lopes
<1%

Major Paulo Roberto
<1%

Maria Madalena Nunes
<1%

Missionário Evandro Craveiro
<1%

Pastor Sena
<1%

Pedro Laurentino
<1%

Tiago Junqueira
<1%

Toinho Dufrango
<1%
Marcelo Castro 53%
Ciro Nogueira 30%
Julio Cesar 16.0%
Alexandre Mariano <1%
$39,672 Vol.
$39,672 Vol.

Marcelo Castro
53%

Ciro Nogueira
30%

Julio Cesar
11%

Alexandre Mariano
<1%

Antônio Barros
<1%

Antônio José Lira
<1%

Cloves José
<1%

Danniel Rocha
<1%

Dionisio Carvalho
<1%

Francinaldo Leão
<1%

Irmão Evandro Marques
<1%

Jardenya Bezerra
<1%

Jorge Lopes
<1%

Major Paulo Roberto
<1%

Maria Madalena Nunes
<1%

Missionário Evandro Craveiro
<1%

Pastor Sena
<1%

Pedro Laurentino
<1%

Tiago Junqueira
<1%

Toinho Dufrango
<1%
This market will resolve according to the candidate who wins the most valid votes of any candidate at the specified election.
Candidates will be primarily ranked by order of valid votes won. If two or more candidates are tied for any position, ties will be broken by alphabetical order of the candidates’ listed full names as they appear in this market. This market will resolve to the candidate that occupies the highest finishing position after applying this ranking.
If the result of this election isn't definitively known 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).
Market Opened: Aug 17, 2026, 6:05 AM ET
Resolver
0x69c47De9D...This market will resolve according to the candidate who wins the most valid votes of any candidate at the specified election.
Candidates will be primarily ranked by order of valid votes won. If two or more candidates are tied for any position, ties will be broken by alphabetical order of the candidates’ listed full names as they appear in this market. This market will resolve to the candidate that occupies the highest finishing position after applying this ranking.
If the result of this election isn't definitively known 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).
Resolver
0x69c47De9D...Marcelo Castro (MDB) holds a modest lead in trader pricing for first place in the Piauí Senate contest, reflecting his status as an incumbent seeking a second term and consistent top positioning in mid-2026 surveys from firms including Amostragem, AtlasIntel, and Vetor. Ciro Nogueira (PP), the other incumbent running for a third term, trails despite name recognition, weighed down by the highest recorded rejection levels among major contenders. Júlio César (PSD) remains competitive as a federal deputy entering the race. President Lula’s September 10 endorsement of Castro and Júlio César during a Piauí event, coupled with indirect criticism of Nogueira, has reinforced the government-aligned candidates’ positioning ahead of the October 4 vote. With roughly 20 registered candidates, elevated undecided shares in earlier polling, and two seats at stake, the market continues to price a narrow contest where late campaign momentum or turnout shifts among key voter blocs could alter the order.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated


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