As usual, Charles Krauthammer nails it. What the really conservative commentators, like the ones at AT, fail to understand is that the Left has worked its "magic" on America since at least the 1930s and FDR, and moving to LBJ and even Nixon's liberal economic policies.
It took Reagan to stop the small tidal wave, but don't kid yourself. He won because of Carter's ineptitude and a bad economy. Plus, if the unemployment rate had not fallen by two full points (from 9.7 to 7.6, as I recall) in 1983, he would not have been reelected in '84. He competed against a divided legislative branch, which shows Americans are not mainly conservative, no matter how much Rush says they are. They like "Game Show Government" which gives away cash and prizes. "Vote for us, and we'll send you a check."
So how does this relate to the 2012 campaign? Americans don't like sudden changes, swerving and jerking back and forth left to right. We're comfortable in the nation we built up, and comfortable (complacent?) people don't like sudden changes or revolutions. The electorate that sits between the 45-yard line thought they were getting a moderate left-of-center Obama, not an Alinsky radical. The anti-Bush. And Obama ran a successful campaign against Bush in '08.
That means Newt, the Sarah Palin types (yes, I know she's not running), Santorum, Bachmann, and Perry could never win a national election, especially against a billion-dollar Obama campaign machine. Perry couldn't because he's perceived as an anti-government (not just a limited government) hyper-conservative, not only because of his drawl and gaffes. And Cain is kidding himself if he thinks he can draw 1/3 of the black vote to his side. I don't think he can get even ten percent. Too much love of "Game Show Government" -- and the same goes for other unthinking left-of-center voters who love the game show.
Therefore, we need a moderate Republican -- or a perceived moderate Republican -- in Mitt. Then after his restoration of the economy, and after eight years, we can then elect a harder line Repubican. Americans don't like sudden changes, left to right. First Mitt, and only then a more conservative Republican like Rubio.