Completely predictable, however. When Warren tied herself so completely to Sanders plan/vision in the first debate(s), she guaranteed this would happen.
Because at some point, she was going to have to differentiate herself from him, or just concede the race on that one issue entirely. All the more obvious, because they are competing for the same voters on this issue.
And this is one of my problems with Warren. It was a stupid thing to do in the first place, but she has a history of making really stupid political mistakes. She just has bad political instincts.
She is a smart woman, but she should have seen this inevitability from the moment she declared, and should have started creating distinctions between her and Sanders plan from day one. It could never be “I agree 100% with everything Bernie says on healthcare, but I am distinctive on these other issues”…because Sanders is precisely the sort of candidate that will gladly continue to move that issue further and further to the left.
And that is precisely what is happening right now. She will never be able to get to his left on healthcare, because he will always move the sidelines even further to the left. And by surrendering control of this topic to him early, she left him in complete control of doing that.