Nice try, but it's so far from the truth you ought to be ashamed of yourself. AK Democrats were promising to bankrupt her family with an endless parade of baseless "ethics" charges, and her "Republican" enemies in Alaska were inclined to let them get away with it. Resigning put a stop to the witch hunts and made better financial sense for her, her family, and her Party.
Here's what you conveniently missed (feel free to apologize, as you've promised): energized a base that probably wouldn't have turned out in 2008 to vote for McCain at all -- and saved some downticket congressmen as a result, raised tons of money for her party and its candidates, gave additional momentum to the Tea Party (which isn't yet done paying dividends by a long shot.)
But by all means do let your PDS run away with you.
Doesn’t matter why she quit. The reality is she quit in her first term as governor. What’s she going to do against a partisan opposition Congress?