During the Democratic primary, the newspaper endorsed City Council leader Christine Quinn, citing her record, over de Blasio, the city's public advocate.
"But it was Mr. de Blasio who proved far better at connecting with voters and at being a persuasive advocate for his ideas," Sunday's editorial endorsement said. "The ideas are good ones: Mr. de Blasio is right on public safety, and on the need to rein in the Police Department's unconstitutional use of stop-and-frisk tactics and restore its frayed ties to the community."
"He is right about the crisis of affordable housing, and he has the most comprehensive plan to attack it. His goal of expanding access to preschool education is a noble priority for the city," the editorial said.
"And he is giving a voice to the forgotten New Yorkers -- the 46 percent living in or near poverty, the 50,000 living in homeless shelters, the millions living outside the zones of economic security and gentrified affluence," The Times said.
While noting New York enjoyed many successes while Michael Bloomberg was mayor, The Times said "its rebirth is incomplete."
"Voters across the boroughs support him overwhelmingly. He promises to be a mayor who listens instead of scolds, who calms fears instead of inciting them," the editorial said. "If he combines his populist touch with attentive, courageous leadership, he will have earned the city's support; he already has ours."
De Blasio faces Republican Joseph Lhota on Nov. 5.