Does he? Maybe
Should he? No
McCain needed a game changer and Palin was a game changer. Perhaps picking Romney or Pawlenty may have gotten him closer, but he would not have won. He needed someone to shake things up, maybe he didn't pick the right person to shake things up but he picked someone who gave him a better chance to win.
Palin was a game changer. However, I think it would be more apporpriate to call her a game ender for McCain. She certainly made my vote alot easier.
the game-ender for McCain was "the fundamentals of our economy are strong." Of course, having Palin making an idiot of herself all over the TV at the same time didn't help.