Yes, what is it about this lady that seems to freak them out. LOL
IMO, it's that they think she can actually win.
And, that she will do what she says she will do, when she does win.
Plus, she doesn't owe the "party" much of anything; she's more likely to give her loyalty to the people who elected her, the voters.
Further, they've thrown everything but the kitchen sink at her for the last two years, and it hasn't stopped her, yet.
If you were a politician, wouldn't that scare you, too?