The twists and turns in Brazil's presidential race end Sunday, at least for a few hours, as millions of Brazilians cast ballots in an election expected to force a three-week runoff campaign between incumbent Dilma Rousseff and one of her two top challengers.

Rousseff held a commanding lead in all recent opinion polls, with her support rising to 46 percent in a survey released Saturday. But it was thought unlikely she could push through to win the absolute majority required to avoid a second-round election.

She'll likely face either former environment minister and senator Marina Silva or Aecio Neves, the former governor of Brazil's second-biggest state. They were deadlocked in the most recent surveys, following Silva's steep drop in polls after aggressive campaigning by Rousseff.

"The fear campaign that Dilma and her marketing people have set up against Marina Silva has had a strong effect," said David Fleischer, a political science professor at the University of Brasilia. "Dilma's people are saying Marina will abolish ... things they've gained through government social programs."

That's the heart of an apparent contradiction of this unpredictable campaign that saw Silva only enter the race in mid-August when a plane crash killed Eduardo Campos, her Social Party's top candidate, with whom she was running as the vice presidential candidate.

Opinion surveys say around 70 percent of Brazilians say they want change — as made plain by mammoth anti-government protests held around the country last year blasting Brazil's woeful public services despite the nation's heavy tax burden.

Yet surveys also find that nearly three-fourths of Brazilians say they are satisfied with their lives.

"They want more of the same and that is what Dilma is offering," Fleischer said.

During the nearly 12 years in power for Rousseff's Workers' Party, strong social programs have helped lift millions out of poverty and into the middle class. Rousseff's strongest support comes from the poorest, those who are precariously hanging onto gains despite an economy that has sputtered during the past four years.

Rousseff promised to expand those programs and to continue strong state involvement in the economy, even though critics complain it creates a poor business environment and the main stock market tumbled every time a new poll showed her on the rise.

Both Silva and Neves offered more centrist economic approaches — such as central bank independence, more privatizations and the seeking of trade deals with Europe and the United States.

Brazilians, who are also deciding congressional races and electing governors, will vote using electronic machines Sunday and results are expected to be known within hours of poll closing at 5 p.m. local time in the country's far west.


Associated Press writer Stan Lehman in Sao Paulo contributed to this report.


Brad Brooks on Twitter: www.twitter.com/bradleybrooks