Brazilians are heading to the polls Sunday for a presidential runoff election pitting rightist Jair Bolsonaro, who was leading in all the polls ahead of election day, and leftist Fernando Haddad.
Some 147 million people are eligible to cast ballots in the election, in which the gubernatorial candidates in 14 of Brazil's 27 states are also in runoffs.
Most of the South American country's 450,000 polling places will close at 5:00 pm, but election precincts in western Brazil will close two hours later because they are in different time zones.
Exit poll results will not be released until all polling places have closed and the national elections commission will then begin releasing the first official vote tallies.
Bolsonaro, according to poll results released on Saturday, was drawing the support of between 54 percent and 56.8 percent of likely voters.
The same polls, however, showed that support for Haddad grew in the past few weeks and he had the backing of between 43 percent and 46 percent of likely voters.
The candidates have completely different visions for Brazil, polarizing the electorate.
Bolsonaro, a controversial army reserve captain and admirer of the South American country's 1964-1985 military regime, has vowed to open up the economy.
Haddad, a leftist intellectual, is promoting policies backed by imprisoned former President Luiz Inacio Lula da Silva.
Brazil's new president will be sworn in on Jan. 1.