Brazilian President Luiz Inacio Lula da Silva won a historic fourth term on Sunday, the country's electoral court said, in a shock result that defied polls and global anti-incumbent sentiment to put the brakes on a wave of right-wing election victories in Latin America.
Mr da Silva, a symbol of the global left and the most dominant force in Brazilian politics this century, defeated Senator Flavio Bolsonaro, the eldest son of former president Jair Bolsonaro.
The senator, who led the election's first round but lost in the run-off by more than four million votes, said he would ask for the result to be annulled owing to a Supreme Court ruling on Sunday that extended voting for two hours.
Mr Bolsonaro's refusal to concede has echoes of his father's reaction after losing to Mr da Silva in 2022. Jair Bolsonaro never accepted his loss at the polls and was given a 27-year sentence for plotting a coup to remain in power.
The scale of Flavio Bolsonaro's defeat by Mr da Silva – by more than twice his father's losing margin – and the fact his campaign also asked for an extension because of rain in the south, make any annulment unlikely, analysts said.
For Mr da Silva, 80, the victory marks another comeback in a career full of them. He was jailed from 2018 to 2019 after a corruption conviction that was later overturned, paving the way for him to beat Jair Bolsonaro in the 2022 election.
He becomes the first candidate since Brazil's return to democracy in the 1980s to be elected after finishing second in the first round of a run-off vote. Previously president from 2003 to 2011, he campaigned this year on a potent mix of pragmatism and populism that has shaped his career in national politics for half a century, introducing reforms aimed at improving the lives of workers and poor Brazilians.
They gained steam with late-campaign pledges including free nationwide weekend public transport, which has to be formally submitted to Congress, and a 15 per cent increase in his trademark welfare programme that is already being put into effect.
Mr da Silva also championed a constitutional amendment that became Brazil's biggest labour reform in decades, which passed with wide support in Congress.