Of course, Mass-Care is a horrible idea with a worse implementation. And it will be seen for what it is before this election cycle is over.
The difference between Romney and McCain is that Romney will acknowledge that “there are problems with the system, and that it’s not suitable for one-size-fits-all National Healthcare but will serve as a learning experience to the states who want to implement something like this”.
McCain, on the other hand will say that the “system worked, and if it didn’t than it’s only because it didn’t have the time or enough money to work, and we have to make sure that with some minor tweaks to the system it’s implemented on a national level before it’s too late for people who are dying or go bankrupt due to lack of medical insurance”.
One additional thought... If Romneycare will be used against him in general election by Democrats, he will not be too proud and ego-maniacal to unconditionally defend it - he’ll admit that it has “a lot of problems, especially if administered by big government bureaucracy” and this will not be damaging to Romney’s candidacy (might even enhance it, admitting that he may have made a mistake as a Governor of very liberal state hellbent on “universal care”) - but this will only seriously damage or kill the idea of National Healthcare idea, nip it in the bud as well as do damage to Democrat candidate running on that platform.
This could be a win-win for Romney and conservatives in general election. I can’t imagine McCain copping to anything wrong in his long government career.