I think that's an obvious problem with the modern democratic party, they don't know what to do, they don't have a really clear message. I don't have any data for this but I'd assume a significant portion of people that vote democrat only do so because republicans are so wildly against progressive policies like universal healthcare and education. And so they're sort of left with a waffley party they aren't very proud of.
My guess, as BlackBellamy suggested, is that in the near future the modern democratic party goes by the wayside and a democratic socialist party emerges because clearly:
https://static01.nyt.com/images/2019...erJumbo-v2.jpg
People are down with it.