Thanks everyone! I think you guys are right in that the white balance I set was for the lights on the monument which were more toward the halogen setting on my camera so that would explain why the moon is blue. I'll try to selectively change the WB for that area, or worst case scenario, I could copy the raw file and do another WB for the moon then cut and paste. I have a feeling, though, that the moon is grossly overexposed so it won't matter so much, but I'd like to try if possible. I suppose worst case scenario, I can just clone out the moon altogether since the sky is basically black anyway....
Regardless, thanks everyone for helping out! And to Douglas of sweden, next time there's a question on who wants to be a millionaire about a blue moon, I know who to call