Poll shows Brazil's Rousseff with seven-point lead in second-round election: Vox Populi

RIO DE JANEIRO (Reuters) - Brazilian President Dilma Rousseff opened a seven-point lead over her main rival, Marina Silva, in a likely second-round runoff in October presidential elections, a poll published on Tuesday showed. Rousseff has 46 percent of voter support in the expected runoff compared with 39 percent for Silva, according to a survey by polling firm Vox Populi. The previous Vox Populi poll on Sept. 15 measured Rousseff's likely second-round support at 41 percent and Silva's at 42 percent, a technical tie. In the first-round vote, Rousseff's voter support rose to 40 percent from 36 percent last week. Silva's support slipped to 22 percent from 27 percent a week earlier. Support for centrist candidate Aecio Neves rose to 17 percent from 15 percent. The Vox Populi poll surveyed 2,000 voters on Saturday and Sunday and has a margin of error of 2.2 percentage points. The results were broadcast by TV Record on the network's nightly news program. (Reporting by Jeb Blount and Luciana Bruno; Editing by Lisa Shumaker)