It is true the race overall is still very close, and Romney still has a good chance, but as you say the non-'rust-belt' maneuver just doesn't work. Besides, his problems in Nevada, Virginia, New Hampshire, and Colorado (in order from least to most likely to Romney) are probably deeper than his just his 'Bain-related' anti-worker problems in Iowa, Wisconsin, Ohio, Michigan, and Pennsylvania (in the converse order).
I don't think any of the darker states above are 'flippable', and of all the flippable states, I think it is clear from polling that all but North Carolina lean from substantially (PA, NV, VA, NH) to slightly (CO, MI, OH, FL, WI, IA) to Obama. The key is, these last five states have only the most subtle polling advantage for the president, and I think Romney could easily flip FL,WI, and IA, but as the original poster points out, this still isn't enough - he still pretty much has to win Ohio.
