Lula, 80, closed his re-election bid with a march through Sao Paulo that his campaign called a record crowd for a closing rally. "Tomorrow, we're going to win the elections in the first round," he told supporters, describing Sunday's vote as a choice between "democracy and barbarism" and promising to "defeat the far right". He has also framed the election as a test of Brazil's sovereignty, warning against "meddling" by Washington.
Bolsonaro, 45, led a motorcycle caravan through towns in Sao Paulo state, echoing the campaign style of his father, before rallying later in Rio de Janeiro. "I am convinced that everything is in place for us to win this election in the first round," he said. The senator is the son of former President Jair Bolsonaro, who is serving a 27-year prison sentence for attempting to overturn his 2022 election loss to Lula, and was photographed at his rally holding a portrait of his father.
The final days of the campaign were also rattled by a bomb scare outside the Supreme Court that led to a scheduled election debate being cancelled.
US President Donald Trump has not formally endorsed Bolsonaro but has said he is watching the election "very closely", a level of interest that has become a flashpoint. Lula's supporters have seized on it as evidence Washington is trying to meddle, while some Bolsonaro supporters, frustrated by the cost of living, say they would welcome US pressure if it helped force change at home.
Polls released on Saturday suggested Lula remained ahead but with a narrowing lead. With neither candidate expected to win outright on Sunday, the race would go to a run-off on October 25 between the two frontrunners, a contest polls suggest would also be close. It is a far tighter race than Lula's 2022 victory, when he beat the elder Bolsonaro by less than two percentage points.
The Bolsonaro campaign also faces scrutiny over a film-funding scandal. Flavio Bolsonaro is under investigation over financing for Dark Horse, a biopic about his father bankrolled by a jailed banker tied to one of Brazil's biggest financial scandals. Brazil's Supreme Court authorised federal police in April to investigate whether he made defamatory statements about Lula.
Bolsonaro has pledged to seek his father's release from prison if elected, and has echoed his father's unsubstantiated claims questioning the reliability of Brazil's electronic voting system, steps analysts have warned could lay the groundwork for contesting the result.