If Palin had not been on the ticket it probably would have been worse, I agree, because her job was to galvanise the die-hard republicans, and she did a pretty good job of that. But do you realise how ridiculous that strategy is? Obama won partly because the democrats were better organised this time round and got THEIR core vote out, but partly also because he persuaded the undecideds and moderates and unsures. If conservatism is relying for electoral victory on just “getting its core vote out” rather than winning over new voters, well...that will work for a short while, but in the long term its a recipe for disaster.
No. Obama won COMPLETELY because they were better organized and got their core vote out, and much of the base was so PO'd at McCain that they would never vote for him. Palin recovered a significant number of those voters, but not enough. There is zero evidence that "undecided and moderate" voters cost McCain the election. The "country club" Republicans (Schwartzenegger and others) have been trying to sell this for the last forty years, and it hasn't worked yet. They had their way completely in this election, with their preferred presidential candidate, and lost their asses.
When Republicans run as conservatives, they win, witness Reagan, Bush I (who lost because he betrayed the conservative position on taxes), Bush II (who ran as a conservative, despite the fact that he governed as a moderate). McCain refused to run as a conservative, and lost his ass.