The survey by polling firm Vox Populi showed Rousseff with 51% of vote intention compared to 39% for opposition challenger José Serra, according to iG website, which commissioned the poll.
The last Vox Populi poll on Oct. 13 showed Rousseff with 48% of voter support and Serra with 40%. Other recent surveys by other polling firms show Rousseff with a lead of between four and seven percentage points.
Undecided voters amounted to 4% in the new Vox Populi poll, which surveyed 3,000 people between October 15 and 17, and has a margin of error of 1.8 percentage points either way. The previous poll showed 6% of voters were still undecided.
While Vox Populi has consistently polled Rousseff higher than other polling firms, the numbers are nonetheless welcome news for her campaign and are likely to be touted by the ruling Workers’ Party as a sign that Serra may have peaked.
The first round of the election on Oct. 3 saw Rousseff fall just short of the absolute majority of votes needed to win as she took 47% of the votes to Serra’s 33%. The third-place Green Party took the bulk of the remainder.
Despite expectations that Rousseff would cruise to victory in the runoff, a re-energized Serra has made a charge in recent weeks as Rousseff has struggled to bounce back from a corruption scandal involving a former aide and voter concerns about her views on social issues such as abortion.
Serra, a former São Paulo state governor of the opposition PSDB party, suffered a setback over the weekend when he failed to win an endorsement from the Green Party, whose candidate Marina Silva took 19% of the votes in the first round. Marina and her party chose to remain uncommitted in the race.