A new BTG/Nexus poll out Monday has Brazil’s October presidential race looking like a runoff from here. In a simulated second round, President Luiz Inácio Lula da Silva has 46 percent and Senator Flávio Bolsonaro 45 percent — a one-point gap inside the survey’s two-point margin of error. Latin America’s largest electorate is, for now, split down the middle.
The first-round picture is clearer and still not decisive. Without influencer Pablo Marçal on the ballot, Lula is at 41 percent and Flávio at 37 percent. Former Goiás governor Ronaldo Caiado is on 5 percent; Renan Santos and Romeu Zema are on 3 percent each. Nobody is near 50 percent of valid votes, which is what Brazil requires to skip a second round. A runoff looks like the default, not a surprise.
Nexus interviewed 2,006 voters by phone from August 21 to 23 for Banco BTG Pactual. The survey is registered with the electoral court as BR-09028/2026. Week to week, the movement is small. Folha notes Lula had 47 percent to Flávio’s 44 percent in the previous runoff simulation; this round is 46–45. That is noise, not a reversal. The race was already tight. Monday’s numbers just refuse to loosen it.
Flávio is a senator and the son of former president Jair Bolsonaro. Lula is the incumbent. A second scenario that includes Marçal, who has registered a candidacy even as São Paulo’s regional electoral court has already declared him ineligible, drops Lula to 40 percent and Flávio to 34 percent, with Marçal at 4 percent. The national electoral court has already cut him off from public campaign funds, debates and free airtime. The pollsters ran the numbers anyway; the legal fight over whether he belongs on the ballot is still ahead.
One house poll is not a forecast, and October is still weeks away. What Monday’s numbers do is freeze the frame: the country’s two poles are close enough that turnout, the smaller candidates and a handful of undecided voters will matter more than any victory-lap speech. For Latin America’s largest economy, that is the story heading into the first round.