RIO DE JANEIRO — President Dilma Rousseff is counting on Brazilians' gratefulness for a decade of progress to overcome concerns about a sluggish economy as the leftist leader seeks re-election on Sunday after a bitter, unpredictable campaign.
Rousseff held a slight lead in one major poll over her center-right opponent, Aecio Neves, but the two were deadlocked in another.
The choice between Rousseff and Neves has split Brazilians into two camps — those who think only the president will continue to protect the poor and advance social inclusion versus those who are certain that only the contender's market-friendly economic policies can see Brazil return to solid growth.
The Workers' Party's 12 years in power have seen a profound transformation in Brazil, as it expanded social welfare programs to help lift millions of people from poverty and into the middle class. But four straight years of weak economic growth under Rousseff, with an economy that's now in a technical recession, has some worried those gains are under threat.
"Brazilians want it all. They are worried about the economy being sluggish and stagnant but they want to preserve social gains that have been made," said Michael Shifter, president of the Washington-based Inter-American Dialogue. "The question is which candidate is best equipped to deliver both of those."
Rousseff and Neves have fought bitterly to convince voters that they can deliver on both growth and social advances. This year's campaign is widely considered the most acrimonious since Brazil's return to democracy in 1985, a battle between the only two parties to have held the presidency since 1995.
Neves has hammered at Rousseff over a widening kickback scandal at state-run oil company Petrobras, with an informant telling investigators that the Workers' Party directly benefited from the scheme.
Rousseff has rejected those allegations and told Brazilians that a vote for Neves would be support for returning Brazil to times of intense economic turbulence, hyperinflation and high unemployment, which the nation encountered when the Social Democrats last held power.
"We've worked so hard to better the lives of the people, and we won't let anything in this world, not even in this crisis nor all the pessimism, take away what they've conquered," Rousseff said before voting in southern Brazil.
After he voted in his hometown in Minas Gerais state, Neves exuded confidence and said he's ready to lead all Brazilians, rich or poor.
"I'm in a much better position than her," he said of his opponent. "We'll show that we'll maintain the social programs, that we'll make good on all our promises. If I win the election, my first big mission will be to unify the country."
In Rio de Janeiro, 43-year-old lifeguard Marcelo Barbosa dos Santos voted in the Botafogo neighborhood and said he's been a Rousseff backer from the beginning.
"Many things changed for the better during Dilma's administration," he said. "The poor have seen our lives improved and we want that to continue."
But Paula Canongia, a 34-year-old hotel owner, said she voted for Neves because of "the current state of our country."
"He's not an ideal candidate, far from it ... but we desperately need change and hopefully he can provide that," she said.
Polls opened at 8 a.m. local (6 a.m. EDT; 10 a.m. GMT). Voting stations in far western Brazil close at 8 p.m. local time (6 p.m. EDT; 10 p.m. GMT), and with the nation's all-electronic voting system, a final result was expected within a few hours.
Associated Press writers Jenny Barchfield in Rio de Janeiro and Adriana Gomez in Sao Paulo contributed to this report.