On the day of the South Carolina primary, I wrote:

Because Huckabee has decided to lay off of McCain, and prior to tonight still had strong polling in a number of Feb. 5 states, Romney faces the daunting prospect of an anti-Romney pact between the two of them, effectively shutting him out of the South on Feb. 5 and then having Huckabee drop out and endorse McCain soon thereafter.  As McCain and Huckabee divide up the spoils of February 5 and work in concert to keep Romney down, Huckabee’s withdrawal and endorsement then throw his supporters and the race to McCain. 

As you have probably all heard ad nauseam over the last few days, this is exactly what has been happening.  One thing that I didn’t foresee was the extent to which Huckabee and McCain are competing for supporters, and that Huckabee isn’t so much sapping Romney’s strength in the South as he is showing his rival a mirage of victory, giving him a tantalising chance to stay in the race that then vanishes into thin air.  Whichever target Romney chooses in his advertisements in several of the Southern states, the voters he drives away from one will likely just go to the other candidate.