Tim Plawenty, Rick Perry, Mitch Daniels, Jim DeMint.
All DOA.
Palin brings out passion among voters. You either love her or hate her. But nobody is indifferent to her. Voters will be indifferent to Pawlenty, Barbour, DeMint, etc because they're promoting the same-old statist agenda. With Palin, you get people actually talking about her in the taverns, arguing at the water-coolers, and engaging in fierce debate about who she is and what her policies are. Inevitably, her detractors will get demoralized at the level of support she draws.
Already, her critics are not talking about how dumb she is or making jokes about her anymore. They're desperately trying to refute her on the issues, and it's failing.
You can dislike Palin all you want, but your opinion is simply in the minority. Palin supporters will go to the corners of the Earth for her. They won't do that with the other GOP candidates.