A definite vulnerability. His winning the Oval is not a given, I think him being the candidate is.
Can he play his flops back to the correct flop? Dreamers is very popular in the immigrant community (and to fiscal conservatives, and to demographically aware welfare statists etc). You can hear the plaintive wail ... "But what about the children???!!!"
I just don't know where the moderate PA voter stands on this, cause that is what matters.