https://www.politico.com/magazine/amp/story/2018/08/01/its-bernies-party-now-219153
“This doesn’t mean that he’ll be the next Democratic nominee for president, or even run. It doesn’t mean that his ideas are good (I personally consider them godawful), or that they will make for a salable platform for the Democratic Party (which I very much doubt).
It does mean that when it comes to domestic policy on the left, it’s Bernie’s world and the rest of the Democrats live in it.
His success represents a version of what has happened to center-left parties around the West, as they have collapsed or been eclipsed by new forces. The two-party system is a durable feature of the American system, so the Democrats aren’t going anywhere, but Sanders is an interloper. As Hillary Clinton complains, he’s “not even a Democrat.”
This is not a cutting attack. Indeed, it doesn’t matter in the least to the Democrats in good standing who are vacuuming up Bernie’s ideas. You can hardly be a U.S. senator who hopes to run for president if you aren’t co-sponsoring pillars of the Sanders agenda such as Medicare for All, free college and the $15 minimum wage.”