The poll, conducted between Sept. 17 and 22, surveyed 5,015 eligible voters nationwide. In the simulated runoff scenario, Lula garnered 47.7 % of support while Bolsonaro received 47.4 %, a difference of just three tenths of a percentage point.
A separate question on a first‑round outcome placed Lula at 45.8 % and Bolsonaro at 43.4 %, with the remaining votes split among Renan Santos (4.5 %), Augusto Cury (2.1 %) and Ronaldo Caiado (1.3 %).
The same pollster’s earlier survey, released a week earlier, had shown Lula at 44.1 % and Bolsonaro at 41.7 % in a first‑round scenario, indicating a narrowing gap as the October 4 election approaches.
Brazil’s electoral system requires a candidate to secure more than 50 % of valid votes to win outright. If no one reaches that threshold, the top two candidates will face a runoff on Oct. 25, a contest that this poll suggests could be decided by a razor‑thin margin.
AtlasIntel reports a margin of error of ±1 percentage point for the poll, meaning the current tie between Lula and Bolsonaro falls within statistical uncertainty. Both campaigns have yet to comment on the findings.