President Jair Bolsonaro's momentum in opinion polls appeared to have stalled after a series of blunders and incidents over the past few days, including the arrest of one of his most outspoken former associates - an episode that turned violent and shook Brazilians ahead of Sunday's presidential runoff.
Leftist challenger Luiz Inacio Lula da Silva, 76, would take 54% of valid votes, which exclude null and blank ballots, compared to the incumbent's 46%, according to an Ipec poll published late Monday. Both were unchanged from a week ago.
Bolsonaro's campaign entered the final stretch of the race on edge following an hours-long standoff between former lawmaker Roberto Jefferson, the ex-president of a right-wing party, and federal police on Sunday.
Jefferson fired a rifle and lobbed grenades at police who had orders to detain him for violating the terms of his house arrest. The outspoken politician was barred from using social media, but just a few days earlier posted a video online comparing a female member of the top court with a prostitute.
Two officers were wounded before he was brought into custody.
The episode poured cold water on market bets that Bolsonaro was soon to overcome Lula in the race and raised concerns about possible post-election violence in the country. The Brazilian real weakened the most in about a month, while shares of state-owned companies sank and drove the benchmark Ibovespa index to lose more than 3%.
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Bolsonaro has repeatedly sought to distance himself from Jefferson since Sunday, saying they are not friends and that whoever goes against the police is a criminal.
The incident capped a series of gaffes by Bolsonaro and his allies that may have contributed to halt the conservative president's upswing since the Oct. 2 first-round vote. Major polls last week indicated the one-time army captain was narrowing Lula's lead, with some surveys suggesting the current and former president were in a dead heat.
Last week, Economy Minister Paulo Guedes enraged voters after unveiling plans to end automatic adjustments to public servant's salaries and pensions according to the rate of inflation. Guedes and Bolsonaro later denied any intention to hurt the spending power of the poor or elderly, but campaign insiders worry about the potential damage ahead of the runoff.
Before that, Bolsonaro, 67, suffered another blow when a video emerged in which the president talks about a visit to a group of "very pretty 14- or 15-year-old" Venezuelan migrants in a poor Brasilia neighborhood, apparently suggesting they were sex workers.
According to an adviser, who demanded anonymity to talk about private strategy, the campaign is concerned that the episodes will hurt Bolsonaro's chances with demographics he's been struggling to win over: low-income voters and women.
Carmen Lucia, the Supreme Court justice who was verbally attacked by Jefferson, is from Minas Gerais, a key battleground state the president is working hard to take after Lula won it in the first-round by nearly 5 percentage points.
Ipec interviewed 3,008 people across Brazil between Oct. 22 and 24, with a margin of error of plus or minus 2 percentage points.