They exterminated their center-right and allowed the SJWs in.
There is no way back from that. It will take decades to expunge those people from the ranks.
In the past the dems had a workable system. The center -right almost always got the presidential nod, and most important spots, the controlled left was able to get theirs as long as they played along and dispensed with the “radical pose”.
Somewhere around 2003-07 the balanced finally tipped to the left, and that was that.
Expunge them? They’re actively recruiting them! Why do you think Keith Ellison — as bigoted a black supremacist as anyone you’d ever meet — narrowly missed being their Glorious Leader?