The Supreme Electoral Tribunal ruled on Thursday that Silva had failed to obtain enough signatures to register her own Sustainability Network party. As a result, the former senator and environment minister could only be a candidate by signing up with an existing political party.
She had until yesterday to make her decision. At a news conference, she indicated she would not be a presidential candidate saying the Socialist Party "already has one," Pernambuco state Gov. Eduardo Campos. She declined to say if she would be his running mate.
A poll conducted in early August by Datafolha, one of Brazil's top polling and statistic firms, said she was the preferred candidate of 26 per cent of registered voters. Rousseff received the support of 35 per cent. Datafolha questioned 2,615 people on August 7-9. The margin of error was plus or minus two percentage points.
Silva won international accolades for her efforts to help preserve Brazil's Amazon rainforest during her tenure as environment minister.
