hmmmm interestingDeidara wins. Once he gets in the air (Mizukage can't stop him) its over. His large bombs will cover enough area to let him either blow up the Mizukage, or destroy the clam which would cancel the Genjutsu allowing him to kill the Mizukage next.
If that fails. C4 is a surefire kill.
Well I guess half the battle for Deidara is realizing what exactly he's fighting. Now Mu was capable of flight and yet was able to draw with the 2nd, so I'm guessing the Mizukage isn't useless against aerial opponents. Too bad we didn't see how the battle went :/