I think he's arrogant. I think he's desperate and is willing to take a risk. I think also that he believes he can go toe-to-toe with Rahm and win. He's from Chicago and they are accustomed to playing rough there, so he probably realizes what a dangerous thing he's doing. He may be gambling that it would just be too difficult and awkward to kill him off. Hard to say if he's right or not.
He is arrogant for sure but I’m anxious to see how his pulling out all the stops will end up. Saying that this will be interesting is probably a gross understatement and nobody should be surprised if he does end up in the river in such poor condition.