* New poll shows Serra 10 points behind Rousseff
* Serra will show experience, knock Rousseff achievements
* Likely hot topics are health, education, security
(Recasts with new poll showing Serra trailing)
By Raymond Colitt
BRASILIA, Aug 5 Brazil's ruling party
presidential candidate Dilma Rousseff surged into her biggest
poll lead on Thursday, piling pressure on her rival Jose Serra
for a sterling performance in the first nationally televised
Former Sao Paulo state Governor Serra, 68, who has debated
in public since he was a student leader nearly 50 years ago,
fell 10 points behind in the new poll as Rousseff gained from
Brazil's robust economy and growing name recognition.
Just six months ago, Serra had a 20 percentage-point
advantage in polls for the October election.
In the debate on TV Bandeirantes on Thursday night, Serra
will try to regain momentum by playing up his experience and
undermining Rousseff's role as energy minister and later chief
of staff of President Luiz Inacio Lula da Silva.
But it will be a delicate balancing act for Serra, who
boasts an Ivy League education and extensive managerial
experience, given that the vast majority of Brazil's electorate
is satisfied with the economy and Lula's government.
"He's got to challenge her without looking aggressive,"
said Valeriano Costa, a professor of politics at Unicamp.
Serra already had an image as arrogant, Costa said.
Rousseff, a technocrat who has never stood for public
office, will face the challenge of emerging from Lula's shadow
and displaying a sometimes absent common touch. But the recent
trend in polls clearly puts the pressure on Serra.
"Serra is more experienced in debates but it's difficult
and he has more pressure to perform," said Costa.
Neither candidate is expected to depart far from Lula's mix
of market-friendly policies and a strong state role.
For a factbox on Brazil political risk click [ID:nRISKBR]
For the candidates' proposals click [ID:nN04266067]
For factbox on recent opinion polls click [ID:nN04275215]
Until Thursday, most polls showed Serra either in a
statistical heat with Rousseff, or trailing by 5 to 8
percentage points. Yet the new Sensus poll showed Serra losing
badly in a hypothetical runoff against Rousseff, by a margin of
48.3 percent to 36.8 percent.
The margin of error in the Sensus poll was 2.2 percentage
In a country with a low penetration of print media,
television is a particularly important campaigning tool, even
though an important local soccer match could cut the debate's
audience in Sao Paulo.
Aware she is less experienced than her rival, Rousseff has
spent the better part of three days rehearsing for the debate.
Asked whether she was nervous, she responded the opposition
candidates would need to take several tranquilizers. She had no
problem discussing health issues with Serra, a former health
minister, but would also focus on public security, an issue
Serra had struggled with when he was mayor of Sao Paulo,
"All Rousseff really needs to do in this debate is to play
conservatively and avoid big mistakes," said Chris Garman,
Latin America analyst with Eurasia Group consultancy.
(Editing by Anthony Boadle)