But as Mr. de Blasio, an activist-turned-operative and now the city’s public advocate, celebrated a remarkable come-from-behind surge, it was not clear if he had won the 40 percent needed to avoid a runoff election on Oct. 1 with William C. Thompson Jr., who finished second. At night’s end, he had won just over 40 percent of the ballots counted; thousands of paper ballots had yet to be tallied, which could take days.
PLUS: Get to know the remaining candidates.