Breaking: Luiz Inácio Lula da Silva set to reclaim Brazilian presidency

Brazilian president Luiz Inácio Lula da Silva will win the country's presidential election, defeating right-wing senator Flávio Bolsonaro in a run-off to secure a fourth non-consecutive term.

The electoral court confirmed Lula's win, as did leading pollster Datafolha.

The shock result defied polls, precedent, and global anti-incumbent sentiment, putting the brakes on a wave of right-wing election victories across Latin America.

With just over 78 per cent of ballots counted, Lula led Senator Bolsonaro, son of imprisoned former President Jair Bolsonaro, with 51.21 per cent to Senator Bolsonaro's 48.79 per cent.

It was a chaotic day for voters in the presidential election.

Polls were initially set to close at 5pm, local time, but were extended by two hours after Supreme Justice Cristiano Zanin accepted a request by Lula's campaign to extend voting, pointing to public transportation issues in three cities in the state of Bahia.

Lula started strongly, and although Senator Bolsonaro overtook him, Lula retook the lead with about half of the votes counted around 8:30 pm local time.

Dr Flavia Bellieni Zimmermann, an international political analyst from Deakin University, said Lula's win would result in "the consolidation of an attempt to have political matters sorted through the democratic process, through the rule of law, through the institutional framework".

Dr Bellieni Zimmermann said the Bolsonaro family represented the right-wing side of Brazil's political spectrum.

"They also represent political forces which have been very much consolidated during the military dictatorship," she said.

"His [Senator Flávio Bolsonaro's] father, Jair Bolsonaro, he is a former military man, and is currently in home arrest because during the 2023 presidential elections, when he lost his re–election bid, there was an attempt of a coup d'etat in Brazil."

She said Senator Bolsonaro was very aligned with US leadership.