When The Impossible Becomes Possible

Ezra Klein can't imagine a Gingrich win:

I think it’s more likely that this mobilization leads to a Romney win then a brokered convention or a new entrant. But I think it makes a Gingrich win almost impossible to imagine. And if something once considered so impossible begins to look likely, then correspondingly extraordinary events — again, like a brokered convention — will become likely, also.