Barack Obama won for several reasons:
#1: When people are likable it's hard to believe they're radical.
#2: When you have a likable candidate and a less likable candidate, and there is apparently little that sets them apart on the important issues that are being discussed in the race, the likable candidate wins.
#3: When values issues are ignored by the "conservative" candidate, they can't help him--or hurt his opponent.
#4: When the so-called "conservative" candidate is running in the shadow of a so-called "conservative" incumbent, and the so-called "conservative" incumbent doesn't actually govern as a conservative--and the so-called "conservative" candidate has a flawed record on conservatism himself, then people can be excused for rejecting so-called "conservatism".
#5: The candidate with the consistent message (e.g. "hope") beats the candidate whose message is still a mystery to voters on election day.
#6: When the more liberal candidate runs on tax cuts he looks like the less liberal candidate.
Note: More reasons to be added to this post as I think of them.