Ross Douthat (Official Chant-Approved Conservative) makes the case that no one can win the GOP nomination, that every candidate is clearly fatally flawed in some way:
McCain is still poison to a large chunk of the base and probably doesn't have enough money to capitalize even if he wins New Hampshire - and if he loses there, he's cooked. Mitt Romney is running on a record that would have made him a moderate Democrat in any state except hyper-liberal Massachussetts. Rudy Giuliani is running on a record that would have made him a moderate Democrat in any place except hyper-liberal New York City. Fred Thompson is more ideologically appropriate, but he's lived down to his lackluster record as a politician by running a remarkably lousy and (perhaps unremarkably) lazy campaign. Ron Paul is, well, Ron Paul.
These guys aren't suited to lead the GOP in a Presidential race. It has to do with who they are as candidates. If Obama doesn't get the nomination it because Hillary beat him and vis versa. Same for Edwards, Richardson and the rest. Giuliani can't get the nomination cause he's a damn liberal on social issues. Huckabee can't win because he's a damn (rhetorical) liberal on economic issues.
Actually, the problem is deeper than that Different GOP candidates represent different parts of the GOP coalition and are unacceptable to others. Mahablog lays it out-
...the top three candidates appeal to separate slices of the Reagan Coalition pie. You’ve got Rudy Giuliani, who has become the great white hope of the neocons. You’ve got Mitt Romney, who has some support among moneyed interests. And you’ve got Mike Huckabee as the Christian candidate. Pat Robertson’s endorsement notwithstanding, Giuliani is simply not going to get the so-called “values” voters. Romney faces hot anti-Mormon prejudice. And apparently Huckabee doesn’t know “The Islamofascist Enemy” from spinach.
Bush combined a love of war, a love of tax cuts and a love of dogma in one neat little package. But this current crop makes the GOP chose. What do you like better tax cuts or war? War or control of woman's bodies? Hurts, doesn't it? Having to pick? Me, I don't have to pick. I get close but not all the way to universal health care and a not-fast enought withdrawel from Iraq no matter which canidate wins the Dem contest.