In terms of actual policy, probably not very much.
Here is a prominent liberal economist’s view of the Democratic primary candidates.
It’s true that Sanders enthusiasts believe that they can rally a hidden majority of Americans around an aggressively populist agenda, and in so doing also push Congress into going along. But we had a test in the midterm elections: Progressives ran a number of candidates in Trump districts, and if even one of them had won they would have claimed vindication for their faith in transformative populism. But none did; the sweeping Democratic victory came entirely from moderates running conventional campaigns.
The usual take on this progressive setback is that it raises questions about Sanders’s electability. But it also has a very different implication: Moderates worried about a radical presidency should cool it. A President Sanders wouldn’t be especially radical in practice.