Talk about a horrible meme for Romney that the only demographic he won decisively was the "incomes over $200,000" group.
Also horrible are the stories that Romney was busing in Mormons from Virginia to pad his rally crowds in South Carolina. Rich Mormons, not a huge base to build on.
The chatter in conservative blogs is that Gingrich will destroy the Party, the Washington establishment and elite media are shoving Romney down our throats, and that they will leave the Party if Romney (Gingrich) gets nominated. I'd feel better about this except I heard it four years ago between the Obama and Clinton factions.
Romney hurt himself by overspending. He flooding the state in robocalls, a dozen calls a day. There was a shitload of mail every day too. My experience is if you hit voters too hard they turn against you.
Romney's release of a couple years of taxes will not quiet the opposition. His tax returns were a symptom, not the disease. If he releases summaries (likely) then the missing information will be jumped on. If his release is voluminous, all the worksheets, every capital gains transaction and every deduction, then it will magnify his too elite status.
The volatility shows a decided lack of enthusiasm. If you supported Mitt yesterday, Newt today, and who knows who tomorrow you are not really supporting anyone. All three primary results so far have been coin flip elections with voters deciding almost randomly in the voting booth.
Romney will probably win Florida, although two days ago I would have used the word "certainly." Early voting and absentee voting can calm the last minute volatility. If Romney does win he will have righted the ship and the Republican power structure can relax. If a late Gingrich charge overwhelms the 200,000 votes Romney has already locked in then we will see a highly entertaining panic reaction out of the establishment.