Yes, I know I know. My prediction record is poor; I said Palin would be the nominee, and she hasn't even run. Palin, despite all appearances, is more shrewd and maneuverable than any of the other GOP'ers. She's the only one in either party who both is a strong media draw, and seems to actually have tapped into the vein of popular disgust over corruption. But Bachmann has always been the most Palin-like candidate; at one point she was called a Palin clone. And she is running, so that removes that.
Here's my theory: The Republicans are looking for a nutter, a purist. That's pretty well established. Romney just won't do. Numerous possibilities, Trump, Perry, Cain, Bachmann, have all been flavors of the week. But whereas Trump, Perry, and Cain were all felled by fatal flaws (not running; immigration & Department-gate; sexual harassment & not even trying) the only reason Bachmann fell from favor is because Perry had entered the race and built up a huge bubble. At the time she was leading, she did come under scrutiny, and the worst thing that could be found was that she has migraines, which is a non-scandal. Yes, she makes nutty remarks on a regular basis, but does the GOP primary electorate really care about that?
Anyone who thinks Newt Gingrich will be the nominee is smoking. He has about five hundred skeletons in his closet, and a hundred of them fell out last week. Not to mention, his stance on immigration at tonight's debate will be fatal. Romney has a hard cap at 30%, and Paul has a hard cap at about 15%. Bachmann will emerge as the anti-Romney and win the nomination. If not for her it would be Santorum.
I do believe you are essentially correct.