Senator Flávio Bolsonaro (PL), son of former president Jair Bolsonaro and the opposition candidate, would take 46.4% of voter intentions in an eventual second round against President Luiz Inácio Lula da Silva (PT), who polls at 46.2%, according to an AtlasIntel/Bloomberg survey released on Thursday, September 10. The 0.2 point gap falls inside the poll's margin of error of one percentage point, which makes the matchup a statistical tie. Blank, spoiled and undecided responses total 7.4%.
In the previous wave of the same tracking poll, Lula had 47.1% and Flávio 42.6%, with 10.3% blank, spoiled or undecided, Estadão reports. In first-round voting intentions, Lula leads with 43% to Flávio's 37.4%, and UOL describes the president as stable in the lead while the senator gains in both scenarios. Augusto Cury (Avante), at 6.6%, and Renan Santos (Missão), at 6.5%, are technically tied behind them. Brazil's presidential race only goes to a second round if no candidate wins an outright majority, which is the stage the poll simulates.
How the poll was conducted
AtlasIntel interviewed 5,000 voters between September 4 and 9 using random digital recruitment over the internet, a method the firm calls Atlas RDR. The margin of error is one percentage point in either direction, the confidence level is 95%, and the survey, funded by the institute itself, is registered with Brazil's Superior Electoral Court (TSE) under protocol BR-01452/2026, according to CNN Brasil.
It helps to separate what is solid from what is provisional. The published figures are a statistical snapshot of the fieldwork week, drawn from a large sample with formal electoral registration. The runoff numbers are simulations, and polls do not forecast outcomes: with a one-point margin of error, gaps of up to two points between candidates carry no real advantage. The 0.2-point difference between Flávio and Lula should be read as parity.
Other scenarios and rejection
The institute tested four more simulated runoffs, all with Lula on one side. Against Romeu Zema (Novo), the former Minas Gerais governor would get 46.2% to the president's 46.0%. Against Ronaldo Caiado (PSD), a 45.7% tie. Facing Augusto Cury (Avante), Lula would be numerically ahead, 43.8% to 41.1%. Against Renan Santos, the president would take 46.0% to the Movimento Brasil Livre coordinator's 33.8%.
On rejection, Lula is the most rejected name at 52.5%, followed by Flávio at 49.6%, Estadão reports, then Renan Santos (35.7%), Pablo Marçal (35.1%), Romeu Zema (31.6%), Ronaldo Caiado (28.1%) and Augusto Cury (25.6%). Former president Jair Bolsonaro (PL), who is not running, stands at 37.7%. Pollsters diverge on the size of Lula's first-round lead: a recent PoderData/Aya survey published by Poder360 has 38% for the president and 36% for Flávio. The first round is scheduled for October 4, G1 notes. The safest way to follow the race is to compare at least two polling firms and always check the margin of error; the full AtlasIntel survey is on file with the TSE under protocol BR-01452/2026.