Mike Stratton, a first-term alder for Prospect Hills and Newhallville, resigned from his seat on the Board of Alders on Monday.

He wrote in a letter to Board President Jorge Perez that he has “exceeded the limit of [his] personal capacity to do this job.” He predicted a bright future for New Haven, but said he cannot stay to assist in bringing that future about because his responsibilities to himself and to his family “must come first.”

He declined to elaborate on his reasons for resigning.

Stratton was a fundraiser and organizer for Justin Elicker FES ’10 SOM ’10 during his unsuccessful mayoral campaign last year. A trial lawyer, he bested Local 34 steward Maureen Gardner in September’s primary race for alder in Ward 19.

Stratton has been a vocal opponent of the majority group of alders backed by Locals 34 and 35, which represent blue-and-pink-collar workers at Yale. In his effort to counter that majority, he organized an alternative team of alders, who called themselves the “People’s Caucus” and promised allegiance to voters alone.