Bill de Blasio, a councilman from Brooklyn running for public advocate, and John C. Liu, a councilman from Queens running for comptroller, easily defeated their opponents in the Democratic runoff election on Tuesday in two citywide races that drew scant interest from voters.
The decisive showings by Mr. de Blasio and Mr. Liu were also a victory for the Working Families Party, the labor-backed group that endorsed both candidates and that mobilized its formidable field operation to turn out voters on a day when most polling sites were largely empty.
And both Mr. Liu and Mr. de Blasio, unlike their opponents, were vocal critics of Mayor Michael R. Bloomberg’s successful effort to persuade the City Council to amend the term limits law so he could run for a third term.
With Democrats dominating New York City’s voter rolls, Mr. Liu and Mr. de Blasio are not likely to face much competition in the November election, and they would fill offices that could quickly make them strong contenders for mayor in 2013. Mr. Liu’s victory keeps him on the path to becoming the first Asian-American elected to citywide office.
Mr. de Blasio scored an overwhelming victory against Mark Green, who was the city’s first public advocate. With 100 percent of the vote counted, unofficial results showed Mr. de Blasio with 63 percent of the vote and Mr. Green with 37 percent.
In the comptroller’s race, Mr. Liu also won easily, with 56 percent of the vote, while David Yassky, a councilman from Brooklyn, had 44 percent.
Mr. Liu, standing with his wife and his 8-year old son at the headquarters of the United Federation of Teachers in Manhattan, thanked his parents, immigrants from Taiwan, for “providing a better life for me and my younger brothers.”
“No one appreciates the wonder and possibility of New York better than me,” he said, his voice hoarse.
Mr. Liu’s long list of thank-yous included labor unions and the ethnic newspapers. Mr. Liu said, “We won this campaign in the streets.”
Mr. Liu, who beat Mr. Yassky by eight percentage points in the primary two weeks ago, drawing on support from union members and Asian and black voters, fended off a late, somewhat unexpected attack from the mild-mannered Mr. Yassky, who accused Mr. Liu of dishonesty.
As a candidate, Mr. Liu, a former actuary, counted on allies he had made speaking out on issues like hate crimes, stands that struck a chord with immigrant and minority groups.
Mr. Yassky, less adept at cultivating a traditional base, promoted his support from the city’s newspapers and his former boss, Senator Charles E. Schumer.
The race turned bitter in its final week, as Mr. Yassky questioned his opponent’s honesty in television advertisements and mailers.
“Would you hire an accountant who doesn’t tell the truth?” a narrator in Mr. Yassky’s ad asked.
In their final debate, Mr. Yassky sought to draw a contrast with his approach to the comptroller’s job, suggesting that he was a stronger advocate for pension reform than Mr. Liu was.
The comptroller acts as the city’s accountant and earns an annual salary of $185,000, manages a staff of more than 700 people and oversees the city’s five pension funds, now valued at about $80 billion.
Mr. Liu, a forceful and sometimes confrontational advocate for reform in city agencies, talked about using the comptroller’s audit power to eliminate waste in government. He will face a Republican, Joseph A. Mendola, in November’s general election.
Mr. Yassky, speaking to his supporters at a club in SoHo, said, “I hope that none of you here will take this defeat as a reason to stop believing in the possibility of politics, and the possibility of good politics.”
Mr. de Blasio will certainly be a more outspoken and visible public advocate than the one he would replace, Betsy Gotbaum, who kept a low profile. Ms. Gotbaum said last October that she would not run for a third term.
In a speech to supporters at a bar in Manhattan near Mr. Green’s campaign office, Mr. de Blasio offered a preview of his willingness to attack Mr. Bloomberg, invoking the term limits fight. “When a mayor ignores the will of the people, we set back the notion of ‘one person, one vote,’ ” Mr. de Blasio said.
As he has done throughout the campaign, Mr. de Blasio promised he would fight for the needy and the working class and stand up “when a mayor ignores the little people.”
“This means supporting senior citizens and the working poor, supporting the homeless and the hungry,” Mr. de Blasio said. “And more than anything, it means protecting our children from danger.”
The public advocate is the city’s ombudsman and second-highest elected official, responsible for monitoring and reviewing city agencies, and is next in line to succeed the mayor if he is unable to serve. Mr. de Blasio will face a Republican, Alex T. Zablocki, in November.
Mr. Green got into the race in February, explaining that even though he vowed in 2006 that he was finished running for office, he was motivated by his anger over Mr. Bloomberg’s move on term limits and his concern about the city’s fiscal troubles.
Overnight, Mr. Green became the front-runner, largely because of his name recognition and a general sense that, as public advocate from 1994 to 2001, he was an effective foil against Mayor Rudolph W. Giuliani.
The mood was subdued at a small gathering at his campaign office, even before the results were announced. Still, there was a cheer when Mr. Green entered the room to give a two-minute concession speech.
Mr. Green said again that he planned not to run for another elected office.
“For now, I’ll go back to writing, commenting, perhaps teaching and Air America Radio to keep the progressive voice strong around the city and country,” Mr. Green said. “You’ll be hearing from me, but not in elected office. I leave that to politicians more skilled than I. For me, campaigns were a route to public service, not an end to themselves.”
Mr. de Blasio, who came in first in the primary on Sept. 15, proved too formidable an opponent. He raised nearly $1.9 million, more than twice Mr. Green’s total, and collected the lion’s share of endorsements from prominent labor unions. On Tuesday, the de Blasio campaign hired 200 voters to promote him throughout the city.
Mr. de Blasio’s connections became ammunition for Mr. Green, who said Mr. de Blasio was a “quintessential political insider” who could not be trusted to be independent.
The race turned particularly negative after the primary. In the final two weeks before the runoff, Mr. Green and Mr. de Blasio sparred in a debate, with Mr. de Blasio questioning the relevance of Mr. Green’s experience, and Mr. Green suggesting that Mr. de Blasio had improperly accepted $33,000 in consulting fees while on the City Council.
William C. Thompson Jr., the city comptroller and the Democratic candidate for mayor, appeared at Mr. Liu’s victory party and exuberantly tried to build excitement for the Democratic ticket heading into the general election.
“Now it is Bill de Blasio, John Liu and Bill Thompson,” Mr. Thompson said. “Looking forward to, on Nov. 3, having a Democratic sweep across the board!”
He then led the crowd in a chant of “Sweep! Sweep! Sweep!”