The leftist incumbent has 47 percent of voter support, according to the survey by polling firm Datafolha, up from 46 percent in the previous poll published on Monday. Support for Neves was unchanged at 43 percent.
While Rousseff has widened her numerical lead to four percentage points, the difference between them is just within the poll's margin of error of plus or minus 2 percentage points.
Excluding undecided voters, spoiled and blank survey responses, Rousseff has 52 percent against 48 percent for Neves, the poll showed, the same result as in Monday's poll, Reuters reported.
Datafolha interviewed 4,355 voters on Tuesday in a survey commissioned by the Folha de S.Paulo newspaper.