President Luiz Inácio Lula da Silva's ruling Workers Party (PT) appeared to have held its ground in Brazil's municipal elections on Sunday but did worse than expected in São Paulo, the country's largest city and the main prize of the day.

The PT won mayoral races in six of 27 state capitals and will compete in the October 26 run-off vote in another three state capitals. The party currently rules eight state capitals totaling 17 of Brazil's largest cities.

Lula's party won the northeastern state capitals of Recife (Pernambuco state) and Fortaleza (Ceará), the southeastern capital of Vitória (Espírito Santo), as well as the northern state capitals of Porto Velho (Roraima), Palmas (Tocantins) and Rio Branco (Acre), official results showed. Party officials said they had also done well in smaller cities and celebrated the election results.

"We are satisfied. This is our best performance yet (in municipal elections)," Paulo Ferreira, PT Treasurer, was quoted by the foreign press.

However in São Paulo, Brazil's financial and industrial capital, Marta Suplicy from PT won 32.5% of the vote, against 33.7% for the incumbent mayor, Gilberto Kassab of the conservative Liberal Front Party (PFL).

An opinion poll on Thursday had projected a 9 percentage point lead for Suplicy over Kassab in São Paulo, a city of 17 million people. Now they must face the October 26 run off.

Suplicy had Lula da Silva's explicit backing, something widely assumed to assure her if not of outright victory, at least of certainty of going into a run-off at the end of the month with a clear lead.

Moreover during much of the campaign Kassab shared the opposition vote in opinion polls with Geraldo Alckmin of the social democratic PSDB.  Alckmin, who lost to Lula in the 2006 presidential election, saw second place taken from him as campaigning progressed and his votes at the end of the month will be decisive.

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