Biography
Dan Koh is the Democratic nominee for the open Massachusetts 6th District seat, having won the September 1, 2026 primary.[1][2][6] He was chief of staff to Boston Mayor Marty Walsh, ran unsuccessfully for Congress in 2018, served on the Andover Select Board, and then worked in the Biden administration as chief of staff to Labor Secretary Walsh and later as a White House deputy cabinet secretary and Intergovernmental Affairs deputy director.[1][2] His campaign website describes a campaign focused on affordability and opposition to President Trump.[3]
Koh was born in Andover, Massachusetts; according to Wikipedia he was born in 1985, the son of physicians Howard Koh and Claudia Arrigg, and attended Phillips Academy.[1][2] He earned a bachelor's degree from Harvard College, where the Harvard Crimson identifies him as a member of the class of 2007, and an M.B.A. from Harvard Business School.[1][2][5] He interned for Sen. Ted Kennedy for three summers and held a one-year fellowship advising Boston Mayor Thomas Menino, arranged through Harvard Business School.[4] Koh served as chief of staff to Arianna Huffington at the Huffington Post, then as chief of staff to Boston Mayor Martin J. Walsh for more than three years, leaving in September 2017.[1][2][4]
In 2018 Koh ran in the Democratic primary for Massachusetts's 3rd District and lost to Lori Trahan by 145 votes (18,580 to 18,435) after a recount.[2][4] He was elected to the Andover Board of Selectmen (now the Select Board) in 2019, receiving the most votes of any candidate, and resigned in February 2021 to join the Biden administration.[2] In 2021 he became chief of staff to U.S. Labor Secretary Marty Walsh, then served as Special Assistant to the President and Deputy Cabinet Secretary, ending as Deputy Assistant to the President and deputy director of the White House Office of Intergovernmental Affairs.[1][2]
As of July 2026, Koh hosted The People's Cabinet podcast.[1][2] He announced his candidacy in October 2025 after Rep. Seth Moulton ran for the U.S. Senate, and won the September 2026 Democratic primary in a six-candidate field with 42.2% of the vote.[1][2][6] He faces Republican Micah Quinney Jones in November.[6]
- 1.Dan Koh · Ballotpedia Reference
- 2.Dan Koh · Wikipedia · 2026-10-21 Reference
- 3.Dan Koh for Congress · Koh for Congress Candidate's own words
- 4.Dan Koh's family taught him government 'should be a force for good' · NBC News News report
- 5.Koh Wins Democratic Primary for Moulton's Congressional Seat · The Harvard Crimson · 2026-09-02 News report
- 6.Dan Koh wins primary for 6th congressional district to replace Seth Moulton · GBH News · 2026-09-01 News report
Researched from the cited sources on 2026-10-21.
On the ballot
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