Brasilia, October 04 (Saba) - Brazil's presidential election will go to a second round after Dilma Rousseff failed to gain the 50% of votes needed for an outright victory, according to Qatar News Agency (QNA).

With 98% of votes counted, President Lula''s former cabinet chief has 47% with Jose Serra trailing on 33%, according to the (BBC). The two will contest a run-off vote in four weeks'' time.

A strong showing by the Green Party candidate, Marina Silva, who polled 19%, may have cost Rousseff a first-round win.

Workers Party candidate Dilma Rousseff is the favoured successor to President Luiz Inacio Lula da Silva, who has completed two terms, and cannot run for a third.

"We are warriors, and we are accustomed to challenges," she said in a speech in Brasilia after the result was announced.

"We do well in second rounds." Rousseff was the front runner for much of the campaign and benefited from Lula''s widespread popularity and the country''s booming economy.

Brazil, one of the world''s most populous democracies, was also choosing local and national representatives. Voting is compulsory in Brazil, with results coming quickly, thanks to Brazil''s electronic voting system.

Saba