Are you sure about that? Santorum or Perry winning would give the momentum to make it a race in South Carolina, where they would likely draw most of their support from Gingrich, turning what is currently a two man race there into a three person race. Gingrich winning Iowa would solidify his position as a frontrunner and make it essentially a two-person race in South Carolina and Florida. While Romney still would have a shot, I think it'd be hard for him to win either against only Gingrich. Meh.
I didn't realize that we weren't working under the shared assumption that after Iowa, Gingrich will be a non-factor. He's squandered his chance at victory there and at this point he'll be lucky if he finishes fifth.
Gingrich doesn't have the money, the organization, the party support, or the endurance to withstand a poor performance in Iowa. If no one else breaks out, he may continue to draw double-digit support in the early Southern contests, but I can't imagine his presence being much of an obstacle to a surging Santorum or Perry.
He could be enough to split the conservative vote in South Carolina like Thompson did to Huckabee last cycle, allowing McCain to win.
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