Nah, Harry wins. He has a wider choice of spells than gandalf, and a bigger sword than any of the hobbits. Mind you, Aragorn might give him a bit of trouble, but hell, he's got a broomstick! Take out Gandalf and Legolas, then fly above the rest, throwing random offensive stuff at them.
Or imperio Aragorn and have him give everyone a good ol' fashioned arse whoopin'.
and the good old Arvada Cardava the good old killing curse that has no defence and only one known surviver









