Brazilian senator Flavio Bolsonaro, son of former far-right president Jair Bolsonaro, finished ahead of incumbant Luiz Inacio Lula da Silva in the first round of Sunday's presidential election, setting up a high-stakes run-off on October 25.

Flavio Bolsonaro secured 47% of the vote, compared with 45% for the incumbent president. The result came as a surprise after opinion polls had projected Lula to lead.
The narrow margin now sets up a direct contest between two sharply opposing political camps, with Lula seeking an unprecedented fourth term and Bolsonaro hoping to bring Brazil's conservative movement back to power.
Flavio Bolsonaro is ‘very happy’
The 45-year-old, Bolsonaro, said he was "very happy" after finishing ahead of Lula and expressed confidence that he could win the second round.
"I am very happy with the real possibility that, three weeks from now, Brazil will give a definitive answer by choosing a modern government," news agency AFP quoted the senator as saying.
A Bolsonaro victory would make Brazil the latest Latin American country to move towards the right, a trend championed by US President Donald Trump.
{{/usCountry}}A Bolsonaro victory would make Brazil the latest Latin American country to move towards the right, a trend championed by US President Donald Trump.
{{/usCountry}}Flavio was relatively little known nationally before his jailed father anointed him as his political heir. He had not previously expressed an ambition to follow Jair Bolsonaro into the presidency.
But the Bolsonaro name helped him consolidate support among Brazil's conservative base, allowing him to edge ahead of Lula despite a campaign marked by scandals and mudslinging.
Lula says 'the game is about to start'
Lula, meanwhile, acknowledged that his first-round setback was unexpected but insisted the race was far from over.
"I admit I was convinced I would win in the first round. The game is about to start. We are in extra time. In extra time, we will win over the Brazilian people," the 80-year-old president said, AFP reported.
The result also came alongside a series of strong performances by the right in parliamentary elections, dealing another major setback to Lula as he seeks a fourth term and attempts to cement his political legacy.
The veteran leftist had framed the election as a battle between democracy and "barbarism", while warning that Brazil's sovereignty was at stake amid US pressure.
Why is the run-off so important?
The first round establishes the two candidates with the strongest support. The run-off then forces voters to choose between those two finalists.
That makes candidates who finished third, fourth or lower particularly important. Their supporters now have to decide whether to back Lula or Flavio Bolsonaro, while the candidates and parties they supported could also endorse one of the finalists.
In other words, the October 25 vote is essentially a fresh election between Lula and Flavio.
The votes from the first round do not carry over. Voters will cast their ballots again, this time choosing between only the two candidates.
With Lula on 45% and Flavio on 47%, the race is therefore still wide open.
Lula's final chance
The run-off is Lula's last opportunity to secure an unprecedented fourth presidential term.
The veteran leftist has already endured a string of political and personal setbacks. He survived electoral defeats, spent 580 days in prison and faced a corruption conviction that was later annulled but continues to be used against him by his political opponents, who taunt him as “Lula the thief.”
He has also faced health scares, including a fall in his bathroom in 2024 that caused a brain bleed.
Still, Lula has maintained that he is in better shape than ever and even dreams of "living to 120."
(With AFP inputs)