Brazilian voters headed to the polls Sunday in a closely contested presidential runoff between leftist incumbent Luiz Inácio Lula da Silva and right-wing challenger Flávio Bolsonaro.

Bolsonaro, a senator and son of former President Jair Bolsonaro, finished ahead of Lula in the Oct. 4 first round, receiving 47.03% of valid votes compared with Lula’s 45.16%. 

Neither candidate secured the majority needed to win outright, forcing Sunday’s runoff.