In his battles with the courts, Bolsonaro has gone so far as to hint at the possibility of a coup. And on September 7 he convened protest marches in which his most fervent followers chanted openly against democracy.

Although they rule out the possibility of a putsch, many analysts say they fear Bolsonaro will reject the election results if he loses the presidential runoff.

“Bolsonaro is a politician who often mimics Trump,” said Freitas, recalling that the Brazilian leader has already warned against electoral fraud by challenging — with no evidence — the reliability of electronic voting, which has been used in the country since 1996.

Stuenkel said Bolsonaro might try to encourage violence as Trump did ahead of the January 6 US Capitol insurrection by Trump followers riled up by his false claims that the November vote was stolen from him.