NEW YORK (CBSNewYork/AP) -- The contest for the Democratic nomination for New York City mayor was not over one day after voters cast their ballots in the primary election.
Public Advocate Bill de Blasio emerged as the top choice in the Democratic mayoral primary on Tuesday, a rather surprising scenario considering just seven weeks ago he had 15 percent of the vote and was in fourth place, CBS 2's Marcia Kramer reported Wednesday.
With 97 percent of precincts reporting, de Blasio has about 40.2 percent of the total vote, which puts him a whisker above the 40 percent threshold needed to avoid triggering an automatic Oct. 1 runoff.
If he cannot maintain that, he will face former city Comptroller Bill Thompson, who has 26 percent, for a potentially grueling three-week, one-on-one showdown with the winner advancing to face Republican nominee Joe Lhota in the general election.
De Blasio Tops NYC Mayoral Primary; Runoff Possible
Baruch College public affairs professor Doug Muzzio said de Blasio scored a deep and broad-based victory.
"Bill de Blasio wins every borough, he wins every demographic, he wins men and women, he wins Hispanics and whites, he wins black women, he wins age groups, income groups, education groups -- you name it, he wins it," Muzzio told WCBS 880's Rich Lamb. "The only demographic that he loses is black men to Bill Thompson."
Muzzio told Kramer de Blasio got a lot of inadvertent help from the man currently in Gracie Mansion.
"Michael Bloomberg helped elect Bill de Blasio. He set himself as the anti-Bloomberg. He defined Chris Quinn as Bloomberg," Muzzio said.
Bloomberg also gave de Blasio a last-minute, and totally unintended, boost when he charged that de Blasio's campaign was "racist."
"In the final days of the campaign, it was throwing a match on gasoline," Muzzio said.
De Blasio Tops NYC Mayoral Primary; Runoff Possible
It may take a week or more before it is known whether a de Blasio-Thompson battle will be fought at all.
On Wednesday morning, both candidates paused to remember the victims of the terrorist attacks of Sept. 11, 2001. De Blasio attended the annual ceremony at the World Trade Center site alongside Gov. Andrew Cuomo, while Thompson attended a service on the Upper West Side.
Lhota was also expected at the World Trade Center site ceremony.
On Tuesday night, de Blasio, who was flanked by the interracial family he made a centerpiece of his campaign ads, made no mention of the potential runoff in his speech to supporters.
Thompson Goes To Court To Request Supervision Of Ballot Counting
"We are better as a city when we make sure that everyone has a shot,'' de Blasio told the raucous crowd. "We begin tonight.''
With de Blasio so close to 40 percent, Democratic leaders may pressure Thompson to drop out of the race in the name of party unity. Exit polling shows that de Blasio would handily defeat Thompson in a runoff, 52 to 34 percent, with 9 percent saying they would stay home.
But Thompson made it clear Tuesday he would compete in a potential runoff.
"Three more weeks! Three more weeks!'' chanted Thompson, the party's 2009 nominee. "This is far from over.''
Thompson, who was endorsed by the Uniformed Firefighters Association, attended the annual 9/11 tribute at the Firefighters Monument on Riverside Drive before turning back to politics, WCBS 880's Marla Diamond reported.
"I think that Bill de Blasio is over 40 percent by about 780 votes and there's still about 16,000 paper ballots to be counted," Thompson said. "I want to make sure that every voice is heard, that every vote is counted."
The Board of Elections estimates the number of paper ballots still to be counted is closer to 19,000.
Bill Thompson Committed To Continuing If Runoff Is Needed
"So we're going to move into court today to order at least court supervision over the ballot counting process," said Thompson.
Baruch College election expert David Birdsell told CBS 2's Tony Aiello that in the "battle of the Bills," "a slight nod to Bill de Blasio for actually eking this out, over 40 percent, but there are many, many plausible scenarios that would put this in a runoff."
Based on 25,000 remaining ballots, Birdsell estimated that de Blasio would have to get slightly more than 32 percent of the remaining ballots to stay at or above 40 percent. If the total number of remaining ballots is closer to 19,000 as some have said, he'd obviously need less of a percentage.
As Kramer reported, there is precedent for an also-ran to drop out of a runoff. In 2005, Fernando Ferrer got 39.5 percent of the vote. Weiner came in second, but he dropped out in the interest of party unity. Ferrer then became the sacrificial lamb to run against the second term-seeking Bloomberg.
On the other side, Lhota beat out billionaire John Catsimatidis to win the Republican nomination for mayor.
"I was the first in my family to go to college and this city has given me great opportunity and as mayor, I will ensure that every New Yorker has the same opportunities," Lhota told supporters.
Lhota wasted no time attacking de Blasio's theme of a "tale of two cities" between the rich and the poor.
"This tale is nothing more than class warfare to divide our city," he said. "I'm not going to let the other side divide our city. I'm going to campaign to unify our city."
City Council Speaker Christine Quinn, the early frontrunner in the race, finished third at 16 percent. She conceded defeat in her bid to become the first woman and first openly gay person elected mayor and congratulated her opponents.
"While we disagree on some issues, we all care deeply about this city and we share the same goal -- greater opportunity for every New Yorker in every neighborhood," she told supporters.
City Comptroller John Liu finished fourth at 7 percent followed by Anthony Weiner at 5 percent.
In his concession speech, Weiner acknowledged that he was an "imperfect messenger.''
"We did not win this time. But I could not be more proud of the campaign that we ran," Weiner told his supporters Tuesday night. "We never backed down. We never ducked."
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