I think you are probably right about Guiliani being toast even if he wins in Florida (a miracle required for that to even happen). But it would muddy the waters a bit more going into Super Tuesday.
If Huckabee were to somehow beat Romney (another miracle needed) in Florida and place second behind McCain that would also muddy the waters quite a bit… but would actually be good for Romney as it would split the Moderate Republican vote more on Super Tuesday. If Huckabee is still seen as “viable” on Super Tuesday, then the Moderates split between McCain (the social moderates) and Huckabee (the fiscal moderates) and Mitt could potentially pull off a landslide win thanks to votes from the hard conservative block vote.
And Huckabee IS going to do well (compared to the money he spent) in Florida due to the large support for the Fair Tax in Florida, but I doubt that he will come close to beating Mitt for second.
I think the breakdown for Florida will be:
McCain wins by 3-4% (mid 30% range of the total vote)
Romney second with around 30% of the vote.
Huckabee 3rd, with around 20%
Guiliani 4th around 15-18%
Super Tuesday presents a real problem for Romney… there are quite a few LARGE left leaning states that vote that day… states where the “typical Republican” is actually a moderate… New York and California come immediately to mind. McCain stands to make a huge forward lurch in the delegate count on Super Tuesday, especially if he comes off a solid win in Florida.
A Romney loss in Florida will be the next step toward the end for Mitt (SC, a very religiously conservative state, being the first step).