Election officials announced Thursday night that won the contested primary for the Governor's Council second district.
Jubinville won the popular vote in many of the 40 towns in the second district.
In the coming months, Jubinville said he plans to speak at local gatherings and hopes to raise support by introducing himself to many area residents.
"We're going to get working right away," Jubinville said. "It feels good that the voters have chosen me and think I'm the best candidate."
Governor's Council is one of the state's oldest elected boards which acts to appoint state officials including judges and parole board members. It also advises the governor on issuing pardons and communications.
As the Democratic nominee, Jubinville will face Republican Earl Sholley in November.