Re-raising is spew, particularly if it's capped back to you with two other callers. You've shown aggression on every street, and this guy is representing a better hand than a single ace; you're very likely behind to two pair or a slow-played set. I would rather call, and possibly make a crying call on the next street, but folding the river unimproved probably isn't bad either (although, without much of a read I tend toward calling down).