Politics requires appeals to emotion. It just does. There are very few people who sit down and read the campaign platforms of the candidates and the parties, set up a spread sheet and analyze the issues pro and con. And frankly, they don't need to. Humans have highly developed systems to evaluate other humans based on a whole lot of sophisticated, subliminal criteria. A good politician's appeal is partly based upon policy, to be sure, but largely people vote for them on tribal identification and personal attraction.
It's complicated but when you boil it down, in American politics, you have two political tribes --- the fear and resentment tribe and the inspiration and progress tribe. I think it's obvious which are which --- it's no accident that the last two Democratic presidents both ran with "hope" as their slogans. People respond to the parties based largely on their own temperament and sense of belonging in that particular tribe. (I had a relative who told me that she didn't really think too much about politics, she just felt that if she voted for a Democrat it would feel like she was a cat having her fur brushed backwards.)
Obama brought out a huge number of people, particularly idealistic young people and African Americans, because of idealism. Although we political junkies were all impressed with his "cool" and his brains, that wasn't the main thing most people found attractive about him. What they saw was that he was the inspirational, living proof of progress and it was a powerful symbol and message.
All successful presidents find ways to keep their own tribe happy while appropriating enough of the other sides' heuristic identifiers to appeal to a few who would normally go with other tribe. But they have to make sure that their own followers maintain their identification with them as well. So Democrats have to keep hope alive. Obama is flirting with failure on that count and I think it's dangerous. His success, and the party's future, depends upon maintaining an enthusiastic base of young and idealistic people long enough for their attraction to Obama to gel into long term political commitment. Because Democrats depend upon inspiration and optimism, it's imperative that they deliver progress. Cynicism, anger and fear either demobilize the base or send some of them to a third party or even the other side. It's a danger that Democrats don't seem ever see and I don't understand why, especially after what happened in 2000. We've seen that it can be fatal.
http://digbysblog.blogspot.com/2009/09/keep-hope-alive-by-digby-i-understand.html