I expect more of a 9 to 1 switchover to Newt. Romney’s not winning North Carolina. Number one, the polls showing where support would move have been nationwide, not within a state. North Carolina voters are backing Newt and Santorum because of conservatism, not anything else that might benefit Mitt.
Why would a state like NC produce an outlier result, particularly given NC went for Obama in 2008 -- if anything that suggests Mittens should do well there.
The best possible split I've seen for either candidate was a Feb. PPP poll that gave Santorum a proportional 2:1 over Romney of 'Gingrich dropout' voters.
"The best thing Romney might have going for him right now is Gingrich's continued presence in the race. If Gingrich dropped out 58% of his supporters say they would move to Santorum, while 22% would go to Romney and 17% to Paul."
Further, let's say Santorum's late-winter surge did come exclusively from Gingrich supporters -- why would those voters just 'go back'? I've seen enough rancor on Free Republic to be assured that will never happen.