Ed Kilgore’s post above clearly highlights one very important aspect of a broader problem: the common assumption in media commentary that trends in voter behavior can be meaningfully condensed into just one or two simple factors like an “enthusiasm gap” or “disappointment.”
To a substantial degree this desire by commentators to present simple explanations is motivated by two factors – the 800 word limit for most political commentary and the desire to propose simple answers of the form “If the Dems would just do X, they could win the election.”
In the case of the “enthusiasm gap,” for example, most commentary quickly lumps all of the “unenthusiastic” Democrats into one of the following three categories (1) left critics discuss the trend as reflecting anger at Obama’s “betrayal” of his campaign promises (2) mainstream commentators point to “disappointment” with the lack of significant change and (3) conservatives explain the problem as clearly reflecting a rejection of Obama’s agenda.
It’s not often noted by political commentators that advertising professionals – the people who are held directly and personally responsible for the success or failure of their communication strategies — generally don’t think this way. Quite the contrary, Ad people are trained to try and segment any overall audience they are trying to reach into meaningful sub-groups with distinct outlooks and then create specific message that speak to those unique perspectives. In many textbooks, copywriters are taught to create a dozen or more “profiles” of audience segments. They are told to write short biographies e.g. “Jessie is a 24 year old graphic designer who lives in a studio apartment with a grey and white cat and furniture she bought at from Rooms to Go….” Often, copywriters and designers cut out pictures from magazines to go with the biographies and hang them on the walls of their offices so that they have a specific visual image of the particular kinds of customers they are trying to persuade.
Faced with a vague concept like “unenthusiastic” Democratic voters, most advertising specialists would immediately think about segmenting the group. Market research would fairly quickly produce a list of subgroups something like the following:

1. People who voted for Obama because of the unique “cool” excitement of the 2008 campaign but who are largely indifferent to politics and never bother to vote in off-year elections.
2. People who voted for Obama out of a sense of profound outrage against some particular aspect of the Bush administration but now do not feel a similar sense of anger compelling them to get out and vote.
3. People who voted for Obama and now feel frustrated with the lack of progress but do not blame Obama himself for the problem. Rather the political stalemate has just made them feel cynical about the value of voting.
4. People who voted for Obama and feel frustrated with him for failing to accomplish more than he has.
5. People who voted for Obama and feel that Obama betrayed them on one or more issues but who still prefer him to the Republicans. They would vote for Democrats if they were standing in the voting booth but have no real enthusiasm for going to the polls.
6. People who voted for Obama but now feel so betrayed by him on one or more issues that they flatly refuse to vote for Democrats.

Looking over this list, it is fairly easy to recognize the quite distinct outlooks of these different “unenthusiastic” Democratic voters and the lack of a simple common view. This quickly suggests one key conclusion:
If you were doing door to door voter canvassing and campaign work, you would vary almost everything in your approach depending on which of these different kinds of voter you were talking to – what you would say, your tone of voice, the degree to which you would express empathy and understanding – all these things would be substantially different depending on the particular person.
This, in turn, leads to one key political conclusion: the most important and effective form of pro-Democratic campaigning this year will be face to face personal communication. There is no single slogan or message that will do the job. The only thing that will reliably influence all these different groups – except perhaps the sixth — is being personally contacted by pro-Democratic advocates who sincerely and passionately insist that voting is still worthwhile.
So let’s stop looking for a “magic bullet” slogan, policy or last minute game-changer. The most important thing Democrats can do right now is person-to-person contact and communication.