Luiz Inácio Lula da Silva has taken a dominant lead heading into Brazil’s presidential election, with polls suggesting the leftwing former leader is within the margin of error for a first-round victory.

Lula, who led the nation for two terms between 2003 and 2010, is projected to receive about 47 per cent of the vote, compared with 33 per cent for incumbent far-right leader Jair Bolsonaro. If Lula secures more than half of valid votes, which excludes blank and spoilt ballots, he can avoid a runoff at the end of October.

Sunday’s election, deemed the most consequential since Brazil returned to democracy in 1985, takes place amid elevated concerns that Bolsonaro may contest the results if he loses. After a campaign marred by sporadic acts of political violence, there are concerns his more radical base could take to the streets in the event of a Lula victory.