SAO PAULO, Oct 28 ― Brazil's leftist presidential candidate Luiz Inacio Lula da Silva maintains the lead over his far-right adversary President Jair Bolsonaro ahead of Sunday's runoff election, according to two polls yesterday that showed the race is roughly stable.

Lula leads by 52.4 per cent of the votes against 46.0 per cent for Bolsonaro, according to an AtlasIntel poll, inching forward from 52.0 per cent while Bolsonaro slipped from 46.0 per cent in the previous poll three days ago.

A Datafolha poll showed Lula widening his lead slightly to 5 percentage points from 4 points a week earlier, maintaining 49 per cent of voter support as Bolsonaro slipped 1 percentage point to 44 per cent.

Analysts say any sign of stability is good for Lula at this point in the campaign with few days for Bolsonaro to catch him.

The number of undecided voters at this stage of the race, and those who say they will vote blank, is down to just 1.6 per cent of the electorate, according to AtlasIntel.

Excluding the undecided and the blank or annulled votes, Lula would win 53.2 per cent of the valid votes against 46.8 per cent for Bolsonaro, the poll said, compared with 53 per cent and 47 per cent respectively in the AtlasIntel survey three days ago.

Lula won the first-round of the election on October 2 in a field of 11 candidates by 48.43 per cent of the valid votes to 43.20 per cent for Bolsonaro.

Pollsters were widely criticised for significantly underestimating support for Bolsonaro.

AtlasIntel recruits voters online and interviewed 7,500 people between October 21-25. The pollster says its survey has a margin of error of 1 percentage point up or down.

Datafolha interviewed 4,580 voters between October 25-27 and its poll has a margin of error of 2 percentage points. ― Reuters