Former state lawmaker and Public Service Commissioner John Driscoll is headed to win the Democratic nomination for eastern Montana’s congressional district.

Driscoll was leading the four-candidate race when it was called by Decision Desk HQ at 10:07 p.m. Trailing Driscoll in unofficial results were Broadus rancher Steve Held, Ming Cabrera of Billings, and Kevin Hamm of Helena.

The district, which includes eastern and parts of central Montana, including Helena, Billings and Great Falls, has an open seat after incumbent Republican Rep. Matt Rosendale declined to run after a brief campaign for U.S. Senate.

Driscoll, 77, is a veteran of Montana politics, having first won election to the Montana House of Representatives in 1972. He served three terms, including a stint as speaker, before he was elected to the Public Service Commission, where he served 12 years.

In the November general election, Driscoll will face Troy Downing, who was declared victor of the Republican primary earlier in the evening by Decision Desk HQ.