* Rousseff leads with 6 percentage points-Ibope poll
* Vox populi shows Rousseff 8 percentage points ahead (Adds details)
By Ana Nicolaci da Costa and Hugo Bachega
BRASILIA/SAO PAULO, Oct 13 (Reuters) - Ruling party candidate Dilma Rousseff held her lead against opposition candidate Jose Serra ahead of Brazil’s presidential runoff election on Oct. 31, two polls showed on Wednesday.
Rousseff, President Luiz Inacio Lula da Silva’s former chief of staff and hand-picked successor, held a 6 percentage point lead over Serra according to the Ibope poll, and a 8 percentage point gap according to the Vox Populi poll.
While Rousseff still enjoys a healthy lead, the results show that she lost momentum from a month ago after failing to snap up an outright victory in the first round of voting.
She obtained 47 percent of the vote in Oct. 3, short of the 50 percent plus-one-vote majority needed, as voters abandoned her camp with doubts over corruption scandals involving her Workers’ Party and over her stance on religion and abortion rights.
The poll results are roughly in line with a Datafolha poll over the weekend, the first to be taken after the first-round, that showed Rousseff with a 7 percentage point lead over Serra.
Full coverage of election: [ID:nBRAZIL]
Election Top News page: link.reuters.com/dux43p
Special report on Rousseff: link.reuters.com/fab25p
Political risks in Brazil: [ID:nRISKBR]
The Ibope poll showed Rousseff with 49 percent of voter support compared to 43 percent for Serra, the former governor of Sao Paulo, according to TV Globo.
She received 53 percent of valid votes against 47 percent for Serra, when null, blank and undecided votes are stripped out, as they are on election day, the poll showed.
In a second poll, the Workers’ Party candidate had 48 percent support compared to 40 percent for Serra. Rousseff also enjoyed 54.5 percent of the valid votes against 45.4 percent for her opponent, according to the Vox Populi poll published by IG Internet portal.
The results could give Serra a further boost, after his campaign got another lease of life when Rousseff failed to snatch a victory in the first round.
Rousseff has tried to reinvigorate her own campaign by going on the offensive, accusing Serra of running a smear campaign against her and lambasting him as a pawn of foreign investors in a debate on Sunday. See [ID:nN10218665].
Just over a month ago, Serra had trailed Rousseff by as much as 20 points, as her campaign was boosted by red-hot economic growth and the support of the hugely popular Lula.
But recent allegations of a kickback scheme involving a former top aide to Rousseff, plus questions among evangelical Christians about her positions on abortion and other social issues appeared to have cost her a first-round victory.
The Ibope poll surveyed 3,010 people between Oct. 11-13 and has a margin error of plus or minus 2 percentage points.
The Vox Populi poll surveyed 3,000 people on Oct. 10-11 and has a margin of error of plus or minus 1.8 percentage points.
Writing by Ana Nicolaci da Costa; Editing by Raymond Colitt