"We predict that the turnout was 83.90 percent," Rizka Halida, senior researcher of Indikator Politik, said here on Wednesday.
The pollster conducted a quick count of voting results at 2,976 polling stations (TPS) spread proportionally across the country, she said.
It selected TPS samples by using a stratified systematic random sampling method.
Based on the quick count results, the Joko Widodo (Jokowi)-Ma'ruf Amin pair collected 54.07 percent of votes and contender Prabowo Subianto-Sandiaga Uno collected 45.93 percent, she said.
Indikator Politik predicted that Jokowi would win the elections.
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