By Paulo Trevisani
BRASÍLIA--Brazil's presidential race is growing tighter, a new
poll showed Tuesday, as a corruption scandal and slowing economic
growth affect the campaign.
Brazilian Socialist Party candidate Marina Silva's lead over
President Dilma Rousseff shrank to a technical tie less than a
month before the vote, according to a survey by the MDA polling
company for Brazil's National Confederation of Transport, or
CNT.
According to the poll, Ms. Rousseff, of the Workers' Party,
would get 38.1% of the vote in the first round on Oct. 5, compared
with 33.5% for Ms. Silva and 14.7% for Aécio Neves of the Brazilian
Social Democracy Party.
Under such a scenario, in which no candidate wins more than 50%
of the total, a second round would be held on Oct. 26 between the
top two candidates. Of the respondents, 45.5% said that in a
runoff, they would vote for Ms. Silva, while 42.7% said they would
vote for Ms. Rousseff. The survey has a margin of error of plus or
minus 2.2 percentage points for both rounds, so that amounts to a
statistical tie.
There are currently 11 candidates in the race.
Compared with the previous CNT/MDA poll, released Aug. 27, Ms.
Silva's lead in the runoff was cut by about half. That can be
explained by Ms. Rousseff's more-extensive television exposure,
pollsters and analysts said.
Brazilian electoral law bans paid advertisements during the
campaign. Airtime is instead allotted to each candidate based on
the number of seats they and allied parties have in Congress. That
formula gives Ms. Rousseff about five times as much exposure as Ms.
Silva.
"Ms. Rousseff has more time to explain her ideas. This is
starting to make some difference," CNT Executive Director Bruno
Batista said to reporters while commenting on the poll's
results.
The CNT/MDA poll is the first released after reports of a
kickback scandal involving state-controlled oil company Petrobras
and allegedly involving prominent politicians who support Ms.
Rousseff.
Reports of the scandal first came out on Sept. 5. The most
recent poll of 2,002 voting-age Brazilians was taken on Sept. 5, 6
and 7. Because the polls were taken so closely after the reports
appeared, some of those polled might not have assimilated the news,
the polling company said.
"The Petrobras news is unlikely to have influenced the results,"
Mr. Batista said.
That could change as more people learn about the allegations,
according to João Augusto de Castro Neves, Latin America director
at Washington-based think tank Eurasia Group. "It usually takes
longer for news, such as the new Petrobras scandal, to be
assimilated by the voters and reflected in an electoral survey," he
said.
It still isn't clear how the scandal will impact each candidate,
analysts said.
Ms. Silva, an environmental activist and former environment
minister, first ran for president in 2010, when she got close to
20% of the vote.
She leapt into the lead in polls late last month after she
replaced Eduardo Campos as the Socialist candidate. Before Mr.
Campos's death in a plane crash on Aug. 13, Ms. Silva, an
evangelical Christian, had been the party's vice-presidential
candidate.
At the time, some analysts suggested her popularity was likely
to decline in subsequent surveys, but she has managed to keep the
lead.
"Marina is becoming better-known, which tends to increase her
rejection rates," Mr. Neves of Eurasia Group said.
Any signs of weakening in support for Ms. Silva could be good
news for the Brazilian Social Democracy Party's candidate, Aécio
Neves, who is now a distant third. Before Mr. Campos's death, Mr.
Neves had been Ms. Rousseff's most serious challenger.
Mr. Neves has focused his campaign on criticizing Ms. Rousseff's
track record on the economy. Economists forecast that Brazil's
gross domestic product will grow 0.5% this year.
Shortly after the CNT/MDA poll was released, Moody's Investors
Service cut its outlook for Brazil's sovereign ratings, citing
tepid economic activity, deteriorating government accounts and a
decline in investor confidence.
The ratings firm lowered its outlook on the country's
government-bond rating to negative from stable. Brazil's rating
remains at investment grade, two levels above junk.
Luciana Magalhães contributed to this article.
Write to Paulo Trevisani at paulo.trevisani@wsj.com