"(The picture for) emerging markets was that of relief and, since the dollar went up by a lot yesterday, it opened trying to take profits," said Fernanda Consorte, a foreign exchange strategist with Ourinvest bank.

The market movement followed a private poll by XP Investimentos that still put far-right candidate Jair Bolsonaro comfortably ahead in the first round, but had a four-way tie for runner-up, including market-favorite Geraldo Alckmin. Bolsonaro and his runner-up are expected to compete in a second round of voting following the vote on Oct. 7.

Still, there was caution on Friday in the lead-up to the release of yet another electoral poll, this time by Datafolha, considered the gold standard in electoral polling in Brazil, that will be released only after the markets close.

While the Brazilian real was up on Friday, making up some of Thursday's losses when the currency closed at an all-time low, the rest of the region's currencies were down against the dollar, particularly the Chilean peso, which was down almost 1 percent.