Each time I look at a graph like this, I think: "Why doesn't Romney pick up any ground in the polls as these clowns successively collapse?"
I would have expected some of the Bachmann people, and sue of the Perry people, and some of the Cain people, and some of the Gingrich people to switch over to Romney as their poll shares collapsed. (The Paulites are another kettle of fish entirely.) But they don't.
The only thing that makes sense to me is that there are an awful lot of people out there I do not see who are putting downward pressure on the Romney poll share: a lot of preachers throughout the land standing up on Sundays and saying: "DON'T VOTE FOR THE MORMON!!"
For the first time, I find myself thinking that Romney might not win the Republican nomination...