Barbs fly in the final week

The last days of the Brazil election have become a bruising exchange of scandals and insults, with incumbent President Luiz Inacio Lula da Silva and challenger Flavio Bolsonaro each scrambling to discredit the other before Sunday's vote, an election expected to be extremely close. The mudslinging has done little to soften Brazil's deep political polarisation, in Latin America's biggest economy and one of the region's last major leftist bastions.

Both men claim the win is already within reach. Speaking on a podcast on Thursday, Lula said he was certain of victory in the first round, dismissing his rival as unfit even "to serve as a building manager". Flavio Bolsonaro matched that confidence, vowing that Lula would be "ousted from the presidency" on Sunday.

The president also handed his opponent fresh ammunition with a comment about prostate screening, saying:

Clips of the remark then swept social media, where it was read as an allusion to abuse, and Flavio Bolsonaro accused the president of being "sexist".

The 'Dark Horse' inquiry dogging the challenger

Flavio Bolsonaro, 45, has stayed a tough foe for Lula despite the revelation that he is under investigation for corruption over the financing of "Dark Horse", a biopic about his father. The campaign forced him to admit that he had asked Daniel Vorcaro, a jailed banker at the heart of one of Brazil's largest financial fraud cases, to bankroll the film.

The voters still to be persuaded

The contest pits 80-year-old Lula against the son of former far-right president Jair Bolsonaro, with little separating the two. The most likely outcome, on current numbers, is a run-off on October 25 between candidates running dead even. Felipe Nunes, director of the Quaest polling institute, said the race is tied "but not at a standstill" and that the final week will determine where voters who can still be swayed will go.

The veteran leftist is chasing a fourth non-consecutive term and insists he is fitter than ever despite his advanced age. He points to falling inflation and unemployment on his watch, and a steep curbing of deforestation in the Amazon rainforest. Yet cost-of-living anger and fatigue with violence and crime run through voters' complaints.

Three voters capture the split:

• •Marcelo Vilanova, 32, a fish market manager in the southeastern city of Juiz de Fora, is voting for Lula as the "lesser of two evils", saying the president's social welfare programmes did good things for him and his family, though he has criticisms of him too.
• •Lucas Sales, 38, who owns a cell phone shop in the same city, is backing Flavio Bolsonaro even if "he himself isn't the best option", pointing to his promise to be tough on crime, a key concern in the election.
• •Gisele Sousa, 45, a clothing shop employee, said "It's really turned into a circus" - and her vote won't go to any of them.

Disenchantment with the choices on offer is widespread among the country's 160 million registered voters.

Trump and the sovereignty flashpoint

Jair Bolsonaro, the former far-right president, is a close ally of US President Donald Trump, who has backed a wave of victorious right-wing candidates in Latin America. On Thursday, Trump said he was watching Brazil's election "very closely". Lula, who has made Brazilian sovereignty a central plank of his campaign, has warned Trump not to "meddle" in his country's elections.

For now, the polls still point to a second round on October 25, even as both candidates insist they can win outright when Brazil votes on Sunday.