Jake Auchincloss, a Newton city councilor and US Marine veteran, formally launched a campaign Thursday for the Fourth Congressional District, adding to the flurry of action that’s quickly consumed the open seat.
Auchincloss is the fifth candidate running to succeed Representative Joseph P. Kennedy III, who is challenging Senator Edward J. Markey instead of seeking reelection.
All five that have formally declared for the Democratic primary hail from Newton or Brookline — the two most-northern communities among the district’s 34 towns and cities — and four of them are under the age of 40.
That includes the 31-year-old Auchincloss, who indicated he’ll build his pitch to voters, in part, around transportation. He planned to launch his campaign at the Newtonville train station, and said in a statement he’d work to tap funding “for Massachusetts to reinvent its transportation system.”
Auchincloss, a former Marine Corps captain, has worked at Liberty Mutual’s innovation lab, where he focused on new trends in transportation and how those changes could affect the insurance industry. His last day is Monday, according to his campaign.
He joins a Democratic field that includes fellow Newton city councilor Becky Walker Grossman, 39; Jesse Mermell, a 39-year-old Brookline resident and a former top Deval Patrick aide; Ihssane Leckey, 34, a self-described democratic socialist from Brookline; and Alan Khazei, the 58-year-old cofounder of City Year, also from Brookline.
State Treasurer Deborah B. Goldberg, another Brookline Democrat, had been preparing her own congressional campaign but decided Wednesday not to run.