BRASILIA (Reuters) – Brazilian ruling party candidate Dilma Rousseff opened a 24-percentage point lead over her main presidential rival in an opinion poll yesterday, staying on course win the Oct. 3 election in the first round.

Career civil servant Rousseff has 51 per cent support, against former Sao Paulo state governor Jose Serra’s 27 per cent, according to an Ibope survey published in O Estado de S. Paulo newspaper.

Rousseff, President Luiz Inacio Lula da Silva’s former chief of staff, has overtaken Serra in his home state of Sao Paulo, which has the country’s largest electorate. She leads there 42 per cent to 35 per cent, the poll showed.

She has doubled her overall margin on Serra since the previous Ibope poll published on Aug. 16, when she led 43 per cent to 32 per cent. She has taken a clear lead in three other polls as well.

Rapid economic growth this year and promises to continue with the policies of Lula, the most popular Brazilian president in recent decades, have helped increase Rousseff’s ratings.

But her lead over Serra got a further boost since the campaign slots started on television this month that have linked her closely with Lula, bringing a first-round victory on Oct. 3 with more than 50 per cent of votes within reach.

The ads have given many voters their first in-depth look at Rousseff, who was little known by the Brazilian public only a couple of months ago. She trailed Serra in the polls as recently as June.