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BRASILIA, Aug 20 (Reuters) - Environmentalist Marina Silva accepted the nomination of the Brazilian Socialist Party on Wednesday, launching a bid for president that has shaken up the campaign for Brazil's Oct. 5 election and threatens the re-election of President Dilma Rousseff.
Silva replaces PSB candidate Eduardo Campos who was killed in a plane crash a week ago, party leaders said.
An opinion poll on Monday showed Silva tied in second place with Aecio Neves of the business-friendly Brazilian Social Democracy Party (PSDB) in a race that will go to a second-round runoff in which Silva could defeat Dilma Rousseff. (Reporting by Anthony Boadle; Editing by Ken Wills)