SAO PAULO: Brazilian President Dilma Rousseff closed ground on opposition candidate Marina Silva in a new poll on Wednesday simulating a likely second-round runoff in October.

The Datafolha survey showed Silva with 47 percent voter support compared with 43 percent for Rousseff, within the poll's margin of error.

Last week Datafolha projected Silva would win the matchup by 48 percent against 41 percent for Rousseff.

Another poll on Wednesday also showed Rousseff and Silva in a tight race if October's elections lead to a runoff vote.

Copyright Reuters, 2014