Bill Thompson has conceded to Public Advocate Bill de Blasio in the Democratic primary race for New York City mayor.
"Today, I'm proud to stand next to a great New Yorker and throw my support behind him," Thompson said.
"I am proud to stand here today and support Bill de Blasio to be the next mayor of the city of New York," Thompson continued.
Thompson announced he would concede during a press conference Monday morning. Rep. Charlie Rangel (D-N.Y.) and Gregory Meeks (D-N.Y.) were among who attended the event.
Thompson addressed issues with vote counting during the announcement, saying it's a "disgrace" that there were issues with voting machines and paper ballots. He said he'd "fight until the very last vote" if this were a general election, but said he was putting his support behind de Blasio because he wants to "return a progressive to City Hall."
N.Y. Gov. Andrew Cuomo praised Thompson during the press conference, saying "it can be much harder to step back than step forward" and praising the Democrat for putting aside his "personal ambition" for the benefit of New Yorkers.
United Federation of Teachers President Michael Mulgrew, who supported Thompson and publicly mocked de Blasio for saying he wasn't burdened by union support, said he's now backing de Blasio.
"Clearly we need to change direction," Mulgrew said, citing the explosion in the number of kids in homeless shelters. "Something is horribly wrong in [this] city."
Republican mayoral candidate Joe Lhota has said he would continue current Mayor Michael Bloomberg's education policies.
"That's all I need to know once I hear that," Mulgrew said, explaining his support for de Blasio.
Below, more from the AP:
NEW YORK — New York City mayoral candidate Bill Thompson conceded the Democratic primary race to front-runner Bill de Blasio on Monday, averting a potential runoff and clearing the way for de Blasio to campaign for the general election.
Thompson endorsed de Blasio at City Hall, saying he was proud to support him as the party's nominee.
The potential runoff had loomed as another act in the Democratic drama over choosing a successor to three-term Mayor Michael Bloomberg – a fight that would keep Democrats tilting at each other while Republicans and independents looked ahead to the general election. With Thompson, the Democrats' 2009 mayoral nominee, out of the race, de Blasio will face Republican nominee Joe Lhota on Nov. 5.
Gov. Andrew Cuomo played a role in brokering the deal, according to two people familiar with Thompson's decision who spoke on condition of anonymity ahead of the announcement.
"New York will be an even greater city under the leadership of Mayor Bill de Blasio," Cuomo said at the City Hall event.
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 second with 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.
He had said as recently 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.
Thompson called the Rev. Al Sharpton, an important city power broker, to inform him early Monday of his decision, according to a person close to Sharpton who was not authorized to speak on his behalf and thus spoke on condition of anonymity.
Sharpton endorsed his longtime friend Thompson during his 2009 mayoral bid but stayed on the sidelines this race, depriving Thompson of a loud advocate in his bid to win the majority of African-American voters. De Blasio and Thompson ran even among African-American voters, according to exit polls.
Sharpton was not expected to attend the morning rally but will likely endorse de Blasio in the coming days, according to the person.
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."
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.
Thompson 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. That count was finished Sunday night and was to be announced Monday afternoon.
The elections board was beginning to count some 78,000 absentee and other paper ballots Monday.
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.
If de Blasio's final vote count ends up below 40 percent, the mayoral primary will also be on the ballot, because Thompson missed the Friday deadline to have it removed.
Lhota ramped up his general election campaign over the weekend and was expected to address de Blasio's nomination later Monday. Adolfo Carrion Jr., a former Bronx borough president running as an independent, will also be on the November ballot.
Michael McLaughlin contributed to this report.
This post has been updated with more from the AP.