New York City mayoral candidate Bill Thompson has conceded the Democratic primary race to Bill de Blasio, averting a potential runoff.
Thompson says continuing the race would be a disservice to supporters, Democrats and the people of New York City in explaining withdrawing his bid for mayor.
He has endorsed Bill de Blasio as the Democratic nominee.
The potential Oct. 1 runoff had loomed as another act in the Democratic drama over choosing a successor to three-term Mayor Michael Bloomberg -- a drama that would keep Democrats tilting at each other while Republicans and independents looked ahead to the Nov. 5 general election.
In unofficial returns with 99 percent of precincts reporting, de Blasio had had 40.3 percent of the vote -- slightly more than the 40 percent threshold needed to win outright. Thompson was at 26.2 percent.
A runoff had long been expected in the crowded Democratic race. But after last week's unofficial returns put de Blasio above the 40 percent mark, Thompson faced pressure to concede and spare the party further division ahead of the general election.
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Thompson said as late as Sunday he would wait until the official tally was finished.
"I think that's important. We want to see every vote counted," he said then.
Currently the city's elected public advocate, de Blasio has been riding a wave of momentum that built during the last month of his campaign, which he billed as "a progressive alternative to the Bloomberg era."
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After lagging in the polls, de Blasio got voters' attention by protesting a hospital closing -- and getting arrested --and airing ads in which his teenage son gave voice to his liberal platform and showed New Yorkers de Blasio's interracial family.
Thompson, a former city comptroller and the only African-American in the race, has run a more centrist campaign, offering himself as a seasoned, thoughtful manager.
He hadn't led in polls of the crowded Democratic field this year, but supporters noted that he had been underestimated in the past: Thompson came much closer than polls predicted to unseating Bloomberg in 2009, despite being vastly outspent.
De Blasio has said Thompson had every right to want the official count.
On Friday, elections officials began checking vote totals from more than 645,000 ballots cast via lever machines that were hauled out of storage for the primary, after the elections board worried it wouldn't be able to reprogram the city's newer, optical-scanner devices for a potential runoff.
More than 16,000 absentee ballots were to be tallied Monday, along with thousands of votes cast with pen and paper after problems at the polls.
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While a runoff had been anticipated, trying to figure out who would be in it had been something like Parcheesi for politics junkies.
City Council Speaker Christine Quinn was the front-runner for months and was jousting with Thompson for second place in polls as recent as early September. Ex-Rep. Anthony Weiner leaped to the front of the pack for a time after getting into the race in May, before the public learned that his X-rated exchanges with women online continued even after similar sexting spurred his 2011 resignation from Congress.
Regardless of the mayor's race, Democrats still will be asked to go to the polls again on Oct. 1. There's a runoff between City Councilwoman Letitia James and state Sen. Daniel Squadron for the party's nomination to succeed de Blasio as public advocate.
— By Associated Press.