BRASILIA, Sept 5 (Reuters) - With polls showing Marina Silva well-positioned to win Brazil's election next month, President Dilma Rousseff's campaign team has taken off the gloves and is painting her rival as a dangerous wild card backed by an out-of-touch financial elite.
Rousseff's campaign managers hope to reverse Silva's dramatic rise in polls by portraying the environmentalist as an obstacle to Brazil's development and a threat to the social gains made under 12 years of leftist Workers' Party rule.
They are taking aim at Silva's weakest flank, her lack of support among the most powerful political parties in Congress, calling her a recipe for unstable government.
And the strategy may be working. Two polls this week showed Silva's surge had leveled out though she remains ahead in a likely runoff, while Rousseff gained some ground and lowered her high rejection numbers.
An icon of Brazil's anti-establishment movement, Silva has captured the support of voters who are fed up with corruption and traditional politicians. She vows to clean up politics and eschews the often murky alliances between the scores of parties in Brazil's political system.
A TV ad run by Rousseff's party this week compared Silva to two former presidents who tried to govern alone and failed. Janio Quadros resigned in 1961 after only seven months and Fernando Collor quit in 1992 before he was impeached on corruption charges.
"Dreams are fine, but elections are when you need to get down to earth and return to reality," the ad says.
Ironically, Collor is now a Rousseff ally.
Rousseff and other government officials have also mounted an offensive against the free-market economic policies that Silva has recently embraced with the aim of restoring business confidence in Brazil. Rousseff warned workers this week that those policies would throw people out of jobs.
In response, a measured Silva accuses Rousseff of engaging in the same kind of scare tactics directed against the Workers' Party in campaigns before it came to power.
More attacks will focus on Silva's proposal to push through a law giving Brazil's central bank full independence, a change that is backed by business leaders but opposed by many Brazilians. Rousseff's camp calls it a maneuver to hand over monetary policy to "oligopolistic" private banks.
"An autonomous central bank will end up putting management of the currency, interest rates and credit supply into the hands of the financial sector," Senator Humberto Costa, who runs Rousseff's campaign in the northeastern state of Pernambuco, told Reuters. "That's just what financial markets want to hear and they identify with her today."
Silva was for long distrusted by investors but she has made concerted efforts to win them over, and the government will try to link her directly to the banking elite.
One of her closest campaign aides and top sponsors is Maria Alice Setubal, a multi-millionaire heiress of one of the families that control Itau Unibanco Holding SA, Latin America's largest bank by market value.
Her brother and current Itau CEO Roberto Setubal said on Wednesday that a Silva victory looked imminent, describing the election as a historic moment that will change Brazil's course.
The daughter of Amazon rubber tappers who taught herself to read at age 16, Silva has become the business class' best hope to end the leftist Workers' Party's grip on power since market favorite Aecio Neves slipped into a distant third place.
Brazil's stock market has rallied on the prospect of Rousseff getting unseated by Silva, who is working hard to persuade voters that she is no longer a militant environmentalist at odds with the powerful agribusiness sector.
Silva was thrust into the race when her party's original candidate, Eduardo Campos, was killed in a plane crash on Aug. 13. Almost overnight, she turned the campaign on its head and polls now show her winning in a second round runoff against Rousseff, who just a month ago looked like she would cruise to re-election.
In the presidential palace, anxiety is running high among staffers who thought their jobs were secure for the next four years and are now being told to get out onto the campaign trail and woo voters.
A senior government official conceded that Rousseff would probably lose the election if it were held in the next two weeks because of the "wave" favoring Silva, but said that could change if the president presents herself as a dependable leader who can build on the social and economic gains of the last 12 years.
"We have to remain calm. There is still lots of time," the official said.
To boost support for the uncharismatic Rousseff, her crowd-pulling mentor and predecessor as president, Luiz Inacio Lula da Silva, has taken to the hustings at her side.
"As long as I have strength, I'll fight to stop the people who did nothing for 500 years coming back to spoil everything," Lula, who is still Brazil's most popular politician, said in a warning to Brazil's elite on a new Twitter account.
Analysts agree Lula will be a huge asset.
"Rousseff has to get to the runoff with the least possible loss of votes, and then use Lula to the maximum," said Thiago de Aragão, a partner at Arko Advice consultancy in Brasilia.
Rousseff's camp intends to zero in on Silva's time as Lula's environment minister, when she clashed with other cabinet members and played a role in delaying licenses for hydroelectric dams in the Amazon that are needed to cover Brazil's growing electricity deficit.
Silva's criticism of fossil fuels will be used to question her commitment to extracting Brazil's vast offshore oil reserves - a source of national pride here - while trumpeting Rousseff's success in getting Congress to assign 10 percent of oil revenues to education.
"Her misguided view of development is another flank where we can confront Marina," said Senator Costa. "We can beat her if we work these points."
But overdoing the attacks on Silva, a frail figure whose health was weakened by malaria and mercury poisoning as a young girl on a rubber plantation, could be counterproductive and add to Rousseff's already high rejection rate in the polls.
"We are not planning to deconstruct Marina Silva. That would run the risk of victimizing her," said a top Rousseff aide. (Additional reporting by Brian Winter; Editing by Todd Benson and Kieran Murray)