SAO PAULO (Reuters) - Brazilian President Dilma Rousseff would win re-election against her most likely challengers without a runoff if ballots were cast today, according to a Datafolha opinion poll published by newspaper Folha de S.Paulo on Saturday.
Rousseff, a pragmatic leftist expected to seek a second term next October, won 42 percent support in a hypothetical matchup against Senator Aecio Neves of the traditional opposition party PSDB and Pernambuco Governor Eduardo Campos, whose center-left PSB party recently bolted the governing coalition.
Neves and Campos, who are still introducing themselves to a national audience, took 21 percent and 15 percent in the poll, respectively.
Their higher-profile party colleagues fared better, underscoring the long shadow cast by more established politicians a year ahead of the 2014 elections.
Jose Serra, the PSDB candidate who faced Rousseff in 2010, and Marina Silva, a former presidential candidate for the Green Party who joined the PSB a week ago, would push the vote to a runoff, according to Datafolha.
In that matchup, which is seen as unlikely, Rousseff polled at 37 percent, Silva took 28 percent and Serra won 20 percent.
The Datafolha poll of 2,517 people had a margin of error of plus or minus 2 percentage points.
In 2010, Serra took about 33 percent in the first round of voting and Silva earned nearly 20 percent. Rousseff won the election in the second round with 56 percent of the vote.
Silva's strong showing in the Datafolha poll also highlights why Campos is expected to share the PSB ticket with her in 2014.
Campos runs the national party and has been considered its likely candidate since last year. Silva's popularity was bolstered by nationwide protests in June over poor public services, as well as her ill-fated attempt to register a new party known as the Sustainability Network.
The unexpected alliance between the two has shaken up next year's presidential race, although they have said the PSB ticket will not be determined until 2014.
(Reporting by Brad Haynes; Editing by Eric Beech)