A union leader, Christophe Mongermont, head of the left-wing Workers' Force.

A representative of the left-wing Workers' Party discussed strategies to press the government to complete a sewer project.

One, with ties to the left-wing Workers' Party, opposes the measure, and is now threatening a general strike, while another, whose members come largely from the private sector, supports its passage.

But Mr. da Silva and his left-wing Workers' Party are hardly the only opponents here to a pan-American, free-trade zone.

According to a Datafolha poll published on Wednesday night, Mr. da Silva, the candidate of the left-wing Workers' Party, is favored by 45 percent of voters.

Among the poor and unemployed, Communists organized groups like the left-wing Workers Sports Association, one of the few ways that working-class youth had access to recreational programmes.

Mr. Dirceu, 56, the leader of the left-wing Workers' Party, declined to be interviewed.

In recent weeks, methanol was banned as a fuel in Sao Paulo and Porto Alegre, two cities with mayors from the left-wing Workers' Party.

Before the free television started, Brazil's television news had generally given unfavorable coverage to Mr. da Silva, a labor union leader who founded the left-wing Workers' Party.

When the left-wing Workers' Party was founded two decades ago and came looking for candidates with grass-roots credentials, she was an obvious choice.