Former left-wing president Luiz Inacio Lula da Silva has a 15-point lead over current right-wing president Jair Bolsonaro, but the latter is closing the gap ahead of the Oct. 2 election, according to a poll released Thursday.
According to the Datafolha institute, Lula has 47% of voting intentions, unchanged from the last poll on July 28, while Jair Bolsonaro goes to 32% against 29% previously.
Lula's lead over the outgoing president, which stood at 21 points in May, has been steadily shrinking.
Both candidates launched their campaigns on Tuesday.
Jair Bolsonaro's government this month increased social assistance for the most vulnerable, and lowered fuel taxes to curb soaring prices.
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Datafolha, who interviewed 5,744 people in 281 cities in Brazil between Tuesday and Thursday with a margin of error of 2%, believes that Lula has a chance of winning the presidential election narrowly in the first round.
In the event of a second round, the left-wing candidate would win with 54% against 37% for Jair Bolsonaro, according to the institute.