I don't count cash advantages primarily because the fact that you receive money is a measure of your support...
Actually, I believe a 2004 study showed that, 95% of the time, the candidate with the most money wins. More money=more supporters.
But that's not all. Until the Palin choice, McCain didn't have the support of his base. I'll certainly grant you that.
As for Obama getting more money because he's run a better campaign, that's not true. Hillary would have gotten just as much money had she been the nominee. The people behind Obama changed the rules midstream, and took away her MI and FL delegates, so Obama became the nominee.
Obama has been getting all of this money because the Democrats knew, just as did the Republicans, that the Dem's were going to win this year. Bush would be a millstone around any Republican's neck, whether it was Huckabee, Romney or McCain.
Given Bush's horrible poll numbers, shouldn't Obama have been much further ahead much earlier? As I said, up until the bailout situation, he was polling within the margin of error when he should have been much further ahead.
Perhaps McCain's announcement to suspend his campaign was a mistake, or perhaps not. The public looks at the financial mess, says "Republicans were in power, McCain is a Republican, therefore it's at least partially his fault."
Also, Obama's "successful" campaign still hasn't clinched the election, although it looks likely. Polling firms like Rasmussen have said that there's about a 5% artificial lead in the Obama numbers that will vanish when people get to the voting booth. IOW, there's a significant number of people who say they're going to vote for Obama, but won't because he's black. From the columnists I've read, the Obama campaign also believes this.
The Obama campaign should have gotten the Ayers, Albright, Rezko issues out of the way very early. They were dormant after the primaries, but they've come back to haunt him.
But the biggest problem with the Obama campaign is that his past can't stand up to scrutiny. No campaign manager can overcome that problem.