Cantor has more experience than Obama.
Assuming that he does have more experience, he’s way behind on the crucial name recognition status, probably way behind any Democrat Obama is likely to tap—precisely because of his own lack of experience.
Although this election is about Obama, McCain is going to have to have a VP who will be a comfortable and reassuring fit with the electorate from Day 1—not a candidate that will get the reaction “Say Who?”
In this race, the Republicans aren’t going to have the luxury of time to spend introducing an unknown. You can only get away with that when you have a very strong candidate in the first chair.