Biden was picked precisely because he was dumb and no threat to his boss (who is also dumb, and runs on ideology alone). However there are limits...
I actually don’t think Hillary would be much of a threat as VP, though. She proved to be a weak, ineffectual SOS, publicly ignored by Obama and hasn’t done herself many political favors by being SOS. While she would be popular with some older liberal ladies, they were already going to vote for Obama anyway, and I don’t think the young find her very attractive. Also, she’s not a good speaker herself. I think Ryan would have no trouble demolishing her.
There’s somebody else I’m much more worried about, but I’m not even going to mention the name.
“I’m not going to mention the name”
Don’t tease, Livius.
Myself, I can’t think of an attractive Dem.
Mayor of a large midwestern city, perhaps?