Brazilians are voting Sunday in a highly polarized presidential election pitting left-wing incumbent Luiz Inacio Lula da Silva against far-right Senator Flavio Bolsonaro, son of jailed former President Jair Bolsonaro.

Axar.az reports, citing the Guardian, that Lula, 80, is seeking a fourth non-consecutive term and has positioned himself as one of the few remaining left-wing leaders in Latin America willing to challenge US President Donald Trump.

Flavio Bolsonaro, 45, is backed by his father’s political base and has frequently praised Trump. He has also pledged to join a US-led anti-drug cartel coalition operating across the region.

The race remains unpredictable, with Lula and Bolsonaro alternating as frontrunners in recent polls. If neither candidate wins more than 50% of the vote, a runoff will be held on October 25.

Brazilians are also voting for state governors, members of state legislatures and Congress, as well as 54 of the country’s 81 senators.