Of course, yet they also want a fight over it. They seek ego-value of a hard won battle.
If their opponent doesn't even put up a fight—if DNC faithful refuse to genuflect at the polls—victory will be far less satisfying.
This is the bully taunting the bullied, getting them to at least try to stand up for themselves, so that they can then have satisfaction of knocking them down.
The more it looks like their targets won't even make a show of opposition, the more the goad comes out.