Former president Luiz Inacio Lula da Silva is maintaining his lead over the incumbent Jair Bolsonaro ahead of Brazil's October presidential election.
Lula drew 47 per cent support according to a Datafolha opinion poll released on Thursday, against Bolsonaro's 28 per cent.
In May, Lula's lead was 48 per cent to 27 per cent.
The polling results suggest time is running out for other candidates hoping to make it a three-way race.
While leftist former state governor Ciro Gomes gained one percentage point from the last poll, he had the support of just eight per cent of voters polled.
In a potential second-round runoff between the rivals, leftist leader Lula now has a 23 percentage-point lead over right-wing Bolsonaro, down from 25 points in May, the survey showed.
This week, Lula presented an official plan outlining government priorities if elected, including a new fuel pricing policy, removing a cap on government spending, and dramatically reining in deforestation.
Lula welcomed Thursday's poll results on Twitter, saying that despite a month of "TV advertising and a flood of fake news on the internet", Brazilian people showed they want to "get rid" of the current government.
Bolsonaro's office did not immediately respond to a request for comment.
Datafolha interviewed 2556 Brazilians of voting age (16 years) on Wednesday and Thursday. The poll has a margin of error of two percentage points.
Australian Associated Press
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