SAO PAULO (REUTERS) - Brazil's leftist President Dilma Rousseff was on the verge of winning a second term in Sunday's election, buoyed by strong support from the poor following one of the country's closest, most divisive campaigns in decades.

Rousseff had 51 per cent of votes in a runoff against Senator Aecio Neves of the centrist Brazilian Social Democracy Party (PSDB), who had 49 per cent support with 95 per cent of the votes tallied, according to official results.

About 2 million votes separated the two candidates.

If the trend holds, it will mean another four years in power for the Workers' Party, which since taking the reins of Latin America's largest economy in 2003 has virtually transformed Brazil.

During that time, economic growth has lifted 40 million from poverty, reduced unemployment to record lows and made big inroads against hunger in what remains one of the world's most unequal countries.

The party's star has faded recently. The economy has slowed dramatically under Rousseff's heavy-handed and often unpredictable policies, making Brazil's glory days of robust growth last decade an ever-more distant memory.

Numerous corruption scandals, high inflation and frustration over poor public services like health care tempted many to consider a switch to Neves' more pro-business agenda.

Yet Rousseff and her supporters spent the campaign warning voters, especially the poor, that a vote for the PSDB would mean a return to the less compassionate, more unequal Brazil of the 1990s - an argument that Neves rigorously denied, but ultimately appears to have prevailed anyway.

"We need Dilma to continue the programs that improve the lives of those in need," said Livia Roma, 19, a university student in Sao Paulo, as she voted on Sunday. "I didn't vote for myself, but for the minorities and less fortunate classes."