William C. Thompson Jr., the former comptroller who is now a Democratic candidate for mayor, hopes a focus on education will help propel him to Gracie Mansion.
On Thursday, Mr. Thompson highlighted the issue with a high-profile addition to his team: Merryl H. Tisch, the chancellor of the state Board of Regents, who will serve as chairwoman of his campaign.
Dr. Tisch, a prominent voice on testing, charter schools and special education, said she had agreed to take on the assignment because she admired Mr. Thompson’s commitment to education.
Mr. Thompson served as president of the city’s Board of Education from 1996 until 2001. As comptroller from 2002 to 2009, he was a frequent critic of Mayor Michael R. Bloomberg’s data-focused approach to overhauling the nation’s largest school district.
“He’s a man of confidence, experience, and honesty, “ Dr. Tisch said during a conference call with reporters on Thursday. “He has the right temperament to lead the city during a very complicated moment.”
Dr. Tisch did not endorse Mr. Thompson in 2009 when he ran against Mr. Bloomberg. Her relationship with the mayor is complex; at times, she has harshly criticized his policies, and at other times, she has rallied to his side.
In addition to her educational expertise, Dr. Tisch brings something of a golden Rolodex to Mr. Thompson. She is a fixture of elite Manhattan society, and her husband, James S. Tisch, is chief executive of Loews Corporation, a conglomerate that includes hotels and oil-drilling operations.
Asked if she foresaw any conflict between her role atop the state’s education board and her work as a political operative, Dr. Tisch demurred.
“We set educational policy for the state,” she said. “We do not run the city’s school system.”
Dr. Tisch, who flirted with her own mayoral bid last year, contributed $4,950, the city limit, to Mr. Thompson’s campaign in January, according to public records.
In past years, she has also contributed to several other people who are running for mayor this year, including Bill de Blasio, the public advocate, and Adolfo Carrión Jr., a former Bronx borough president.