Hyper-partisans
"some of them are hyper-partisan Democrats who have decided that Trump won't ever be their president"
As I recall, there were many hyper-partisan republicans who decided the same about Obama and probably would have decided the same about Hillary. There's always going to be zealots who will never be convinced. The question is will Trump recognise that he won the presidency but not the popular vote, and try and govern for all, or will he decide that a mandate is a mandate, and govern purely for the benefit of those who voted for him, or more likely for the benefit of himself and his friends?