President Romney agrees with you after that spectacular 2010 performance.
Romney was a loser and was only chosen because the field was very weak. The GOP base tried-on every other candidate, which is why there was a new flavor-of-the-month every month. We tried Perry, Cain, Newt (and several others I can't recall), but they were all duds.
Romney was just the least embarrassing dud, so he was reluctantly chosen as the nominee. But he was an extremely weak candidate and stood for nothing but flip-flopping.
Obama was beatable in 2012, the GOP just didn't have any good candidates running. And, the problem continues to this day - there is not a seasoned GOP candidate that excites the base. And the only ones that do excite the base (e.g. Cruz) are way too bombastic to be presidential material.