Former Biden official wins primary for open Moulton House seat in Massachusetts

Democrat Daniel Koh is projected to win his party’s primary for the House seat left open by Rep. Seth Moulton (D), according to Decision Desk HQ.

Koh was locked in a tough primary battle against progressive state Rep. Tram Nguyen for the seat representing the state’s 6th Congressional District. Moulton, who has represented the district for a decade, opted to leave his seat and challenge Sen. Ed Markey (D).

He led Nguyen by 10 percentage points with 68 percent of the vote reported Tuesday evening — nearly 41 to about 30 percent — per DDHQ.

Four other candidates were on the Tuesday ballot, including veterinarian Mariah Lancaster who dropped out over the weekend and endorsed Nguyen.

A White House official under President Biden, Koh notched high-profile endorsements from the former president as well as former Vice President Kamala Harris and former Transportation Secretary Pete Buttigieg, among others. Nguyen received support from Democratic Massachusetts Reps. Lori Trahan and Ayanna Pressley as well as The Boston Globe.

Koh is almost certain to win the blue seat representing the northeastern portion of the state. He will face off against Republican Micah Jones, a lawyer and Army veteran, who ran unopposed for the GOP nod.

In 2018, Koh ran in Massachusett’s 3rd Congressional District, losing to Trahan. He previously served as shief of staff for Boston Mayor Marty Walsh.

The mayor later became Labor secretary under Biden before resigning to run the National Hockey League Players’ Association. Koh served as Walsh’s chief of staff in Washington before joining the White House’s Office of Intergovernmental Affairs.