Brazil's ruling party presidential candidate Dilma Rousseff, the country's former Chief of Staff, led the latest poll for the first time. Rousseff got the support of 40 percent voters, compared with 35 percent for the main opposition's candidate, former Sao Paulo governor Jose Serra, and 9 percent for Green Party candidate Senator Marina Silva, according to a poll released Wednesday by the National Industry Confederation (CNI) and consulting company Ibope. The poll also measured the rejection level of each candidate. A total of 23 percent of the electors said they would not vote Rousseff, while 30 percent would not vote Serra and 29 percent would not vote Silva. The poll was carried out on June 19-21 among 2,002 electors from 140 municipalities. The Brazilian presidential election will take place in October. 