PROVIDENCE, R.I. — Many elected Democrats have drifted left since the party’s shattering defeat last November, turning to a brand of progressive politics that is closer to Senator Bernie Sanders’s democratic socialism than the more market-friendly liberalism that characterized the Obama era.

But when the nation’s governors gathered here over the weekend for their annual summer meeting, a group of pragmatic Democrats took center stage. And now one of them is taking the first steps toward seeking the presidency in 2020.

“I believe the time is right to lend my voice, the voice of someone that after getting elected has been able to govern in what’s viewed as a red state,” Gov. Steve Bullock of Montana said in an interview. “Some of the things that I’ve been able to do in Montana can also translate beyond just the state’s border.”

Mr. Bullock is creating a federal political action committee, Big Sky Values PAC, that will offer a political infrastructure to let him meet Democratic donors, contribute to the party’s candidates and fund his out-of-state electoral travels.