President Luiz Inacio Lula da Silva won a landslide victory giving him a powerful mandate to press his anti-poverty campaign, but corruption scandals dogging his leftist party and thinner support in Congress could mar his second term.

Silva's re-election to another four years Sunday reflected the support of tens of millions of poor Brazilians who rewarded him for easing poverty while improving the economy in Latin America's biggest nation.

Beaming as he wore a white T-shirt emblazoned with "It's Brazil's Victory," Silva promised to boost growth and reduce Brazil's wide gap between the rich and poor.

"We're going to do a lot better in my second term than we did in the first," Silva said following his victory over center-right rival Geraldo Alckmin, the former Sao Paulo state governor.

After repeatedly denying knowledge of corruption allegations that slammed his Workers' Party during the campaign, Silva acknowledged the party faces a tough road ahead and must regain the prestige it once enjoyed as Brazil's most ethical party.

"From now on we do not have the moral, ethical or political right to commit errors," Silva told 5,000 cheering supporters in a late-night street party on Avenida Paulista in the heart of Sao Paulo.

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With 99.9 percent of the vote counted, Silva had 61 percent support and Alckmin 39.

While he wants to push important pension and tax reforms through Congress, Silva's legislative support has diminished since he first took office in 2003. His party, known here as the PT, lost several seats in Congress and will remain under investigation after the election because of the latest scandal — plans by top members of the Workers' Party to pay $770,000 in cash for an incriminating file about Alckmin's allies.

Silva will have to deal with a host of thorny issues, from the back-to-back corruption scandals to criticism that Brazilian growth has lagged behind other Latin American economies'.

The Workers' Party has grappled for two years with charges of vote-buying and illegal campaign financing. Although Silva was never personally linked to the scandals, they hurt the reputation of the former labor leader and lathe operator.

The scandals reinforced suspicions of government corruption that prevented Silva from a first-round election victory on Oct. 1, when he failed to get the 50 percent plus one vote required for an outright win.

Even Silva's supporters said they expected more from their president over the next four years.

"We know there was corruption, so the first thing he'll have to do is get rid of corruption in the PT and in the government," said Riquelme Wallen Alves Brandao, a 23-year-old Sao Paulo resident who voted for Silva.

Silva's popular Family Allowance program gives monthly payouts to 11 million poor families. Although the program was started by his predecessor, he dramatically expanded it in a move analysts said translated into guaranteed votes.

Silva also managed to reduce Brazil's notoriously high inflation through high interest rates, and even prices of staples like rice and beans dropped.

Analysts from Sao Paulo to Wall Street have praised Silva's economic policies, but say he has more work ahead to decrease unemployment that stands at 10 percent.

Economic policy during Silva's second term "should remain more or less in the same line as before, but Silva will have to implement policies to increase growth and decrease unemployment," Fleischer said.

Silva said he believes Brazil's economy can expand as much as 5 percent next year and that Brazilians are "fed up with being an emerging power" with boom-and-bust economic cycles.

Silva, a leftist who has governed as a centrist with conservative economic policy, is considered much more moderate than strident South American leftist leaders like Bolivia's Evo Morales and Venezuela's Hugo Chavez.

He disappointed the United States by backing away from talks to form a Free Trade Area of the Americas, stretching from Canada to Chile, but relations with the United States aren't expected to suffer, analysts said.

"The United States lived peacefully with Lula during the his first four years and there's no reason it won't live peacefully in the next four," said Alexandre Barros, an analyst with the Brasilia-based Early Warning political risk consulting group.