Polling conducted by CNT/MDA puts Flávio Bolsonaro, the Rio de Janeiro senator, narrowly ahead of incumbent president Luiz Inácio Lula da Silva in a simulated 2026 Brazilian presidential runoff, with the gap between the two candidates standing at just one percentage point — 50.5% against 49.5% of valid votes cast.

Released on 16 October, the survey placed the two camps so close together that the gap between them fell within the range statisticians treat as too narrow to call. Polling work was carried out by the research firm MDA on behalf of the CNT — Brazil's National Transport Confederation, a federation representing business interests in the sector.

The poll drew on responses from 2,002 voters aged 16 and above and was carried out between 13 and 15 October, carrying a sampling margin of plus or minus 2.2 percentage points, according to the broadcaster's coverage. Polling figures released by a news outlet placed Flávio Bolsonaro at 46.8% of total voting preferences, with Lula trailing at 45.9%, while 4.9% of respondents opted for blank or null ballots and a further 2.4% remained uncommitted. Of the ballots counted — excluding those left blank or otherwise invalid — the split landed at 50.5% against 49.5%.

Data from the CNT/MDA poll released on 3 October placed Lula ahead in a runoff scenario by a margin of 47.3% to 43.1%, according to a news channel. Across all voting-intention categories, Flávio's share climbed by 3.7 percentage points while Lula's fell by 1.4.

Polling from multiple firms points to a contest that remains within the margin of error. Two polls released within a day of each other placed Flávio narrowly ahead: Datafolha, publishing on 15 October, put him at 51% against 49% in valid votes, while Quaest's figures from 14 October showed him leading 46% to 44% when all ballots were counted.

When two candidates land within a poll's margin of error, their numbers are too close to declare a clear leader. A margin of error of 2.2 points on each figure leaves the poll unable to establish a clear leader between the two candidates. Because polling methods and interview windows vary from one survey to the next, any single set of results captures public opinion only at the particular point in time when those respondents were contacted.

Polymarket, a platform where users place wagers on real-world outcomes, placed Flávio Bolsonaro's probability of taking the 25 October runoff at 76.5%, with Lula's corresponding figure standing at 22.5%, as of 2:17 p.m. ET on 16 October. Trading volume across the platform reached a combined value of approximately US$184.7 million. Runoff contracts are also available on Kalshi, a trading platform operating under CFTC oversight in the United States.

Whether late-breaking developments — among them the Senate's passage of legislation abolishing the 6×1 working week — shifted voter opinion remains unclear, as fieldwork for the poll wrapped up on 15 October. How much opinion has shifted will become clear only when the next round of surveys is published.

How the 2.4% of respondents who told pollsters they had yet to make up their minds will vote on 25 October, or whether they will show up at all, remains an open question. Polling data captures attitudes at a given moment rather than predicting how any vote or outcome will ultimately unfold. Polling work on the survey was carried out by MDA at the request of the National Transport Confederation (CNT), a business federation based in Brazil. Under the reference BR-00652/2026, the filing holds formal standing before the electoral court.