Brazil opens the first round with Lula and Flávio Bolsonaro short of a majority

Brazilians began voting at 8 a.m. local time on Sunday in the first round of a presidential election that the main pollsters do not expect to finish in a single day. Stations close at 5 p.m. Brasilia time. A candidate wins outright only with more than 50 percent of valid votes. Blank and null ballots do not count toward that total. If nobody clears the bar, the top two meet again on 25 October.

President Luiz Inácio Lula da Silva, 80, is seeking a fourth term. Senator Flávio Bolsonaro, 45, is the main challenger. He is the son of former president Jair Bolsonaro, who is serving a 27-year sentence for plotting a coup after the 2022 defeat and has endorsed the senator from house arrest. Voters are also choosing all 513 seats in the Chamber of Deputies and 54 of the 81 Senate seats, two-thirds of the upper house.

The last published surveys leave both men short of a first-round majority and close to each other in a likely runoff. Datafolha, which interviewed 4,006 people on 2 and 3 October with a margin of error of 2 points, put Lula at 45 percent of valid votes and Flávio Bolsonaro at 42 percent. In a runoff the same poll had 47 to 46. CNT/MDA, 2,007 interviews from 30 September to 2 October, had Lula at 47.8 and the senator at 42.1 in the first round, and 47.3 to 43.1 in a second. Quaest, 3,702 interviews on 2 and 3 October, had the first round at 46 to 45 and the runoff the other way, 44 to 42 for the senator. AtlasIntel's final pre-election poll, 5,005 voters from 23 to 28 September, had Lula at 46.2 percent of valid votes to 43.1.

The rest of the field has not broken the pattern. Datafolha gave Ronaldo Caiado 4 percent, Renan Santos 3, Augusto Cury 3 and Romeu Zema 1. CNT/MDA had Cury at 3.6, Caiado at 3.4, Santos at 1.7 and Zema at 0.9. Reuters noted that both leading candidates are rejected by roughly half of voters, which is why a third name has not consolidated the dissatisfied middle.

Every presidential election since 2002 has gone to a runoff. Datafolha's last 2022 first-round poll put Jair Bolsonaro at 36 percent of valid votes. He finished near 43. That miss is the practical warning for Sunday's count. Electronic urns report quickly, but late shifts of a few points have decided who looks like the favourite on the Monday after a first round.

The campaign has been thin on programme. Reuters reported that both frontrunners skipped the main television debates. The subjects that did land with voters were a corruption scandal, crime, and the public accounts. The next government inherits high public debt and a weak growth outlook, whoever wins. Trade and security disputes with Washington have also sat inside the campaign. A Flávio Bolsonaro win would extend a run of right-wing victories in the region by candidates aligned with President Donald Trump. A Lula win would leave those disputes in place.

The Senate renewal matters as much as the presidential number for the next term. With two-thirds of the chamber on the ballot, the winner of 25 October will not automatically control the votes needed for constitutional amendments or for senior appointments that require upper-house consent. The Chamber turns over in full. State-level machines that delivered the 2022 runoff still decide large blocks of those seats.

Counting rules are simple and easy to misread in the first hours. Valid votes are the denominator. A candidate on 49 percent of valid votes with a large pile of blank ballots has not won. Overseas voters and the last states to close, in the west of the country, can move a tight first-round margin by a point or two. The electoral court publishes the running total as urns transmit. A concession or a claim before that transmission is complete has no legal effect.

The open question on Sunday night is not only who leads. It is whether either man can get close enough to 50 percent of valid votes to change the three-week campaign that the polls already assume. If the gap in the first round is inside a few points, the runoff starts as a turnout contest among voters who have already rejected both names once.