Heraldo de Madrid - Brazil presidential battle enters home stretch

The confrontation will happen in a late-night, live broadcast on TV Globo just hours after a fresh opinion poll will signal voter intentions ahead of Sunday's first election round.

Far-right Bolsonaro, 67, is seeking reelection after a controversial first term, but polls to date have shown him lagging behind ex-president Lula, 76, who left office in 2010 with an unprecedented 87-percent approval rating.

The incumbent is counting on his evangelical and business-centric support base, while Lula -- who served two consecutive terms from 2003 -- is appealing to poor, minority and anti-Bolsonaro voters.

The TV Globo debate, traditionally the most-watched pre-electoral program in Brazil, will be the last chance for candidates to sway undecided voters, who, polls suggest number just 13 percent of the electorate.

With voting in Brazil compulsory, a Datafolha poll from a week ago showed Lula strengthen his lead with 47 percent of stated voting intentions over 33 percent for Bolsonaro.

- 'Can change the picture' -

A winning candidate would need to garner more than 50 percent of valid votes cast -- excluding spoiled or blank ballots -- to avoid a second, conclusive round of voting on October 30.

Bolsonaro's camp expect him to adopt an aggressive stance towards Lula in Thursday’s final debate, focusing on the corruption scandals that have damaged the leftist Worker's Party, and pressing home his conservative values on issues of religion and abortion.

The pair will be joined on stage by five other candidates with no statistical shot at making it to the final two.

"This is the debate that can change the picture," a Bolsonaro campaign member told AFP on condition of anonymity.

After the first debate, a month ago, Lula was criticized for seemingly evading the corruption question. He was further harmed by not taking part in another debate, last Saturday, between Bolsonaro and other candidates.

Lula has urged Brazilians loyal to any of the minority candidates -- all with less than 10 percent of voter intention -- to rather cast a "useful" vote for him, and against Bolsonaro.

Thursday's poll by Datafolha, the lead reference in Brazilian politics, was conducted among 6,800 respondents, a higher number than usual.

It will bring out another, final poll on Saturday, the eve of the first round, that could indicate whether the debate has made any difference.

The broadcast election campaign in Brazil ends at midnight on Thursday, although in-person events and distribution of election material will be allowed until Saturday night.

Bolsonaro has repeatedly hinted that he will challenge any result in which Lula is the winner, saying last weekend: "We are the majority. We will win in the first round."

L.Herrero--HdM