Why Flavio Bolsonaro Beat the Polls in Brazil's First Round — and What It Means for the Runoff

Brazil's presidential race has been thrown wide open after Senator Flavio Bolsonaro defied the pollsters and edged ahead of President Luiz Inacio Lula da Silva in the first round of voting, a result that has reshaped expectations for the runoff now just three weeks away.

Heading into Sunday's vote, most recent surveys had Lula leading by roughly three percentage points and entering a second round from first place. Instead, Bolsonaro captured about 47 percent of the vote to Lula's 45 percent — a reversal that caught analysts off guard and triggered fresh scrutiny of what shifted in the campaign's closing days and what the polls may have failed to capture.

According to Carlos Pereira, a political scientist at the Getulio Vargas Foundation think tank, one key explanation lies in a late wave of support from voters who had initially planned to back smaller right-wing candidates. Bolsonaro himself appeared to anticipate this dynamic, telling reporters on election day that he expected a "protest vote" from people united chiefly by their opposition to Lula.

Pereira noted that Brazilian voters typically cast sincere ballots in the first round and strategic ones in the second. This time, however, that strategic consolidation happened earlier than usual. Supporters who might have backed figures such as Ronaldo Caiado, the former governor of Goias, or Renan Santos, the businessman who founded the right-wing Free Brazil Movement, instead decided to throw their weight behind Bolsonaro immediately. As Pereira put it, these voters reasoned that if they were going to support Flavio in the runoff anyway, there was little reason to wait.

That early consolidation carries a double-edged implication. Political analyst Rafael Favetti told Reuters that some of the support Bolsonaro would normally have picked up only in a second round had already been "front-loaded," which could leave him with less room to expand his coalition in the coming weeks.

A second factor, Pereira said, was the sprawling Banco Master scandal, an alleged banking fraud that unsettled both campaigns in the final stretch and touched figures across Brazil's political spectrum. Among those drawn into the controversy was Supreme Court Justice Alexandre de Moraes, who had overseen the case that sent Bolsonaro's father, former President Jair Bolsonaro, to prison. De Moraes faced accusations of improper ties to Banco Master owner Daniel Vorcaro after documents surfaced appearing to show the banker seeking legal advice from him. De Moraes has denied the allegations.

Pereira suggested that connection may have served as a late trigger for some voters. Bolsonaro's supporters have long viewed Moraes as a political ally of Lula, and Flavio himself sought to link the two on the campaign trail earlier this year, declaring that anyone voting for Lula was effectively voting for Moraes. A September Datafolha poll found that 34 percent of Brazilians associated the Banco Master scandal more with the left, compared with 27 percent who tied it more to the right.

Andre Pagliarini, a history and international studies professor at Louisiana State University and author of a book on Lula, agreed the scandal may have damaged the president. He argued that a campaign dominated by a spectacular and unrelenting scandal touching seemingly the entire political class played directly to Bolsonaro's strengths as an anti-institutional insurgent. Pagliarini also pointed to an irony at the heart of the race: Flavio Bolsonaro was himself directly implicated in the Banco Master affair in ways Lula was not. The younger Bolsonaro is under investigation over allegations that he sought money from Vorcaro to finance a film about his father. He denies any wrongdoing.

Yet neither analyst viewed the outcome as a straightforward failure of polling. For Pagliarini, the bigger surprise was the sheer scale of right-wing support, which extended far beyond the presidential contest. Bolsonaro outperformed his father's 2022 first-round result by nearly four percentage points, while his Liberal Party emerged as the largest bloc in Brazil's Senate. The right also performed strongly in gubernatorial races and made significant inroads in the country's southeast.

Pagliarini attributed part of that success to a potent information environment surrounding Flavio's campaign, which allowed his message to stay in front of voters even as mainstream outlets reported scandal after scandal. In his view, the polls if anything underestimated how firmly committed right-leaning voters already were.

Beyond the tactical and scandal-driven explanations, the results also expose a deeper challenge for Lula and the Brazilian left: a widespread perception that the government is not delivering enough, especially on the economy and public security. On paper, Lula can cite record-low unemployment, falling inequality and easing inflation. But those indicators have not translated into a sense that daily life is getting easier, as many Brazilians continue to feel squeezed by high food prices and mounting household debt. A September Quaest poll found that nearly half of those surveyed believed the economy had worsened.

With the runoff approaching, both camps now face a compressed and high-stakes contest. Bolsonaro must convert his first-round momentum into a broader coalition despite having already absorbed much of his potential support, while Lula must reverse a late drift toward his rival and address the economic anxieties that appear to have cost him votes. The questions raised by Sunday's result — about polling accuracy, voter psychology and the durability of the right's resurgence — will hang over Brazil until the final ballots are counted.