Brazil's main opposition candidates

President Luiz Inacio Lula da Silva faced a challenge from several rivals in the first round of the presidential election on 1 October.

The following are profiles of the three main opposition candidates: Geraldo Alckmin - who will challenge Lula again on 29 October - Heloisa Helena and Cristovam Buarque.

GERALDO ALCKMIN

Geraldo Alckmin, 53, is standing for the centre-left Brazilian Social Democracy Party (PSDB), a party which he helped found. The PSDB forged an election alliance with the Liberal Front Party in June. A doctor by training, he got into local politics at the age of 19, and was mayor of his home town Pindamonhangaba, Sao Paulo, at 23.

Since that time he has been a state deputy, served two terms as a federal deputy and been elected vice-governor of Sao Paulo. His most recent post is governor of Sao Paulo, the country's largest and most populous state, which he assumed in January 2001 when the previous governor died. Nicknamed "Chuchu", he resigned as governor in March to run for president.

HELOISA HELENA

Heloisa Helena is a former member of President Lula's Workers' Party (PT), and is now running against him as the presidential candidate for the Socialism and Liberty Party (PSOL). The 44-year-old divorcee from the small town of Pao de Acucar in Alagoas trained as a nurse and taught at the Federal University of Alagoas.

She was elected senator for Alagoas state in October 1998 for the PT but was expelled from the Workers' Party bloc in the Senate in June 2003. Her refusal to follow the party line and support a social security reform bill led to her complete expulsion from the PT in December 2003. She co-founded PSOL with other expelled PT members. Her candidacy is backed by the Communist Party (PCB) and the Unified Socialist Workers' Party (PSTU).

CRISTOVAM BUARQUE

Cristovam Buarque, a mechanical engineer and economist, was born in 1944 in Recife and is the presidential candidate of the Democratic Labour Party (PDT). He is another former member of the Workers' Party (PT), from which he resigned in September 2005 citing disappointment with Mr Lula's handling of a corruption scandal. Elected to the Senate in October 2002 on the PT ticket, he jumped ship to the centre-left PDT.

A minister of education between January 2003 and January 2004 in the Lula administration, he was also governor of Brazil's Federal District, including the capital, Brasilia, from 1994-98, when he failed to win re-election. Prior to entering politics he worked for the Inter-American Development Bank and the University of Brasilia.

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