Who the heck is the mole...?

Craig, Mark, or Nicole? I think it is Mark. He has kept the most money out of the pot. And i believe he tried at the end of the season to try to get all the exemptions. But i am not sure. My girlfriend thinks it is Craig. Why couldn't they just do it all tonight. Ugh, so annoying. (i know ratings.) So who is the mole? I'm stumped.