By Anthony Boadle
BRASILIA (Reuters) - Brazilian President Dilma Rousseff's approval ratings are recovering from a wave of popular discontent and she has broadened her lead over other possible contenders in next year's election, a poll published on Tuesday showed.
However, her negative numbers remain high enough to force a run-off vote, which could still complicate a re-election bid.
Rousseff's approval rating, which was in the 70's before the massive street protests that shook Brazil in June, recovered to 58 percent at the start of this month, from 49.3 percent in July, according to the poll commissioned by private transport sector lobby CNT and conducted by MDA Pesquisa.
Approval of her government's performance has risen to 38.1 percent from 31.3 percent in July, the survey showed.
In an outburst of anger against politicians of all stripes, hundreds of thousands of Brazilians took to the streets in June to protest against corruption, mismanagement of government money, the high cost of living and poor public services.
Rousseff has scrambled to improve public transportation, health and education services, while pushing for reforms to make the country's political establishment more accountable.
The latest poll showed that two in every three Brazilians believe her government has acted to meet the demonstrators' demands.
Rousseff's controversial program to improve medical attention in remote and poor parts of Brazil by bringing in foreign doctors, mainly from Cuba, was backed by 73.9 percent of those polled.
On the downside, 75.9 percent of Brazilians think inflation has not been brought under control, the poll showed, a perception that undercuts the government's credibility as it strives to revive a slow economy.
Rousseff's recovery in the polls will strengthen her ability to keep spending pressures from legislators in check and may give the central bank more room to raise interest rates "without feeling political heat," said the Eurasia consultancy in Washington.
"But it also reinforces complacency. We no longer think a change in the economic team to shore up credibility is likely," Eurasia said in a note to clients.
The latest poll confirmed a trend by other recent surveys that point to a recovery in Rousseff's popularity as she heads toward a widely expected re-election bid in October 2014.
Her negatives have come down, with 41.6 percent of those polled saying they would never vote for her, down from 44.7 percent in July. For MDA pollster Marcelo Costa Souza, that is still not enough to avoid a run-off with an uncertain outcome.
Rousseff's main potential rival, environmentalist Marina Silva, continues to gather steam. Voting intentions for Rousseff increased to 36.4 percent from 33.4 percent in July, compared to 22 percent for Silva, who edged up from 20.7 percent in July.
Support for the likely candidate of the main opposition party PSDB, Aecio Neves, remained unchanged at 15.2 percent, while that for Eduardo Campos, the governor of Pernambuco state, slipped to 5.2 percent from 7.4 percent in July.
Silva, a former environment minister, is not identified with Brazil's traditional political establishment and the recent protests have boosted her standing. Silva came third in the 2010 election, winning 20 million votes as a candidate for the Green Party. She has since founded a new party, but it is not certain that she can register it in time for the 2014 election.
The poll of 2,002 people was conducted between August 31 and September 4, and has a margin of error of 2.2 percentage points.
(Editing by Doina Chiacu and Christopher Wilson)