But on Sunday, Ms Silva announced at a party convention in Sao Paulo that she would endorse neither candidate.

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Both she and her husband, a senator for Sao Paulo, belong to her party's moderate wing.

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She won in a run-off against former Sao Paulo governor Jose Serra with 55.9% of the votes.

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In 2001 he made international headlines after one of his six daughters, Patricia Abravanel, was kidnapped as she left her house in an exclusive area of Sao Paulo.

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"She has already spoken to Robinho and we have people in Sao Paulo picking her up, " the player's agent, Wagner Ribeiro, told Reuters news agency.

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She said she believes the spiral of violence began in May when the Sao Paulo state government took a more aggressive stance against the PCC and drug gangs.

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