Mark McKinnon: 'Mr Invincible' facing fight to convince true conservatives
Mitt Romney's presidential campaign looks to be gathering pace. But he has also been giving his doubters and opponents some serious ammunition.
For a short time after the votes were counted in Florida last week, Mr Romney appeared to be the runaway Republican frontrunner, with a huge primary victory and likely to quickly wrap up his party's nomination for president.
But in the space of 24 hours, he morphed instead into a hobbled and defective candidate, likely to have to slog it out for several more months before stumbling forward to the general election in a substantially crippled fashion.