De Blasio, one of six Democrats vying for a shot to replace Mayor Michael Bloomberg, picked up 39 out of 67 votes from club members at the meeting at the Church of the Intercession in Washington Heights.
"This club was founded in early 2009 and Bill de Blasio has, I think, been to every event we've ever held," said club founder Mark Levine, who is vying for a City Council seat in the 7th District. "He's really been present in the club and cultivated the club and that paid off tonight."
Louise Katz, 81, of Washington Heights, said de Blasio had her support even before the meeting began.
"Everything that a mayoral candidate has to worry about, he has the right progressive attitude," Katz said.
De Blasio, who lives in Brooklyn, has been active in Northern Manhattan during the campaign, participating in several uptown debates and meeting privately with Northern Manhattan parents in April.
Comptroller John Liu placed second, picking up 18 votes.
An April Quinnipiac poll found that de Blasio was in third place among Democrats, behind City Council Speaker Christine Quinn and former U.S. Rep. Anthony Weiner, who has not formally announced his campaign.
Other endorsement winners at Monday's club meeting included Manhattan Borough President Scott Stringer for city comptroller, Levine and Ydanis Rodriguez for the 7th and 10th council districts, respectively, City Councilman Robert Jackson for Manhattan borough president, incumbent Cyrus Vance Jr. for Manhattan District Attorney, Denise Dominguez for civil court judge and Brooklyn City Councilwoman Letitia James for public advocate.