All the candidates were hosting election night rallies in venues across the city. Each gathering went silent for 15 minutes when President Barack Obama addressed the nation on the situation in Syria.
Quinn, who was bidding to become the city's first female and first openly gay mayor, was the front-runner for much of the year, boasting the biggest campaign war chest and strong establishment backing. But she has been dogged by her support to change term limits to let Bloomberg run again in 2009, a decision unpopular with liberals who make up the bulk of Democratic primary voters.
Turnout appeared light, but the city's complaint line received several thousand voting-related calls. Many reported jams and breakdowns in the antiquated lever machines, which were hauled out of retirement to replace much-maligned electronic devices.
The mayoral campaign was waged in hundreds of candidate forums and across millions of dollars of TV ads and was largely fought on the legacy of the Bloomberg era. Substantial policy differences were scarce among the Democrats, who agreed that the school system needed an overhaul, that the city's poor had been forgotten, and that stop-and-frisk police tactics used to stop suspicious people needed changing amid claims that police unfairly targeted blacks and Latinos.
Thompson nearly defeated the billionaire mayor four years ago. This year, he ran a quiet, centrist campaign with hopes of receiving enough support from minorities to reach the runoff.
Weiner surprisingly entered the race in May after being in political exile since resigning from Congress in 2011 upon admitting to lewd online exchanges with women who were not his wife.
His candidacy sparked curiosity and popular interest, and he immediately shot to the top of the polls. But support collapsed almost as quickly when he revealed in July that he continued the online behavior even after his resignation from federal office.
Associated Press video journalist Ted Shaffrey and Associated Press writers Jim Fitzgerald and Jake Pearson contributed to this report.
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