It is pretty sad actually. There are still hold outs in major media outlets that think that being linked to the democratic party is an insult. They are blind to the fact that the American people have endorsed the largest democratic majority in (I don't know how big this is historically, but it is damned big).
You can't find a republican where I live, not anymore. They're conservatives, or libertarians, or whatever else they can think of not be called a republican. They'll even break themselves into the single issue group that got them into politics, like "I"m an NRA member" etc..
They are not republicans anymore.
So, go ahead and label anyone who upsets you and your dying party. I'm sure McCain doesn't care, he never liked you in the first place. I'm sure he's more concerned with jumping into the narrative of history, not as the face of republicanism, but as the guy who overcame the ideas of the past to work with a new president.
McCain doesn't want to be the bad guy in that movie.
He'll let the endangered republican party do that.