Senegalese President Abdoulaye Wade was unable to secure a third term in office following a weekend runoff vote. He admitted defeat after most of the opposition candidates backed challenger and Sall, the BBC reports.
The BBC described Sall as a political protege of Wade's, though both sides fell out of favor in part because of the public spending habits of Karim Wade, the president's son.
Sall described the victory as a "new era" for the Senegalese people.
Wade secured the right to seek a third term after a court ruled he was exempt from a term limit because the laws were adopted after his inaugural election in 2000.
The United Nations said it had evidence that at least four people, including a police officer, were killed in political violence in the wake of the announcement.
Sall said he'd impose a five-year term limit for the presidency if elected.
He won 26.5 percent of the vote compared to 34.8 percent for Wade during the first round of voting in February.