President Luiz Inacio Lula da Silva's chosen candidate, Dilma Rousseff, looked certain to succeed him as president of Brazil after a runoff vote Sunday. Polling stations opened at 8:00 am (1000 GMT), with Brazil's 135 million voters called out to make a choice between Rousseff, Lula's 62-year-old former cabinet chief, and her opposition rival, former Sao Paulo state governor Jose Serra, 68. Voting is compulsory in Brazil.