Preliminary election results suggest he won 68% in the 20 March presidential run-off which pitted him against former First Lady Mirlande Manigath. Final results are due on 16 April at the earliest.
The 49-year-old flamboyant musician is a political novice but is confident performing in front of crowds.
Promising change in a nation devastated by a 2010 earthquake, he has gained a loyal following, being especially popular among younger voters.
Despite being politically inexperienced, his message of reform has appealed to Haiti's poor and unemployed, correspondents say.
While he has held no formal position in the field, he has been politically active, holding speeches and taking part in demonstrations.
He has been a vocal critic of former Haitian President Jean-Bertrand Aristide, who recently returned from exile.
During his campaign, he pledged to build houses in a country where tens of thousands still live in makeshift camps more than a year after the quake, which killed at least 250,000 people.