Ahmadinejad will pass himself as the Mahdi
When he will feel strong enough, Ahmadinejad will have it announced by his accomplices that he is the long awaited Mahdi (or he will set up some puppet he can control, but I doubt he will pass such a carefully orchestrated opportunity). He is already paving the way to his "ascent" by promoting and circulating rumors about his "aura" and the ecstasy of his listeners. He will also try to destroy Israel to force other Arab countries to recognize him as the 12th Imam. By becoming holy, a living saint, a prophet, he will also pre-empt al Qaeda's dream of an imperial caliphate and will dictate (in his dreams) to all Muslims.
Security Council sanctions or other strong-arm tactics at this point should be pursued just for the sake of "appearances" but will only increase his charisma. The only way to go, IMHO, is to support the Iranian people by all means available while carrying out covert sabotage operations inside Iran to weaken the regime.