1. Dem affiliation has declined measurably since the election, raising the number of identified independents to its highest level in 70 years. While GOP indicators are down, the fact that the Dems are likewise declining in this environment shows they are doing something wrong.
2. Dems continue to believe the myth of the short American political memory. The idea is you can do crap like AIG bonuses and failing to pass cram down early because people won't remember later on. This is significantly less true than politicians believe. While voters may overlook some specifics, the accumulation of disappointments erodes enthusiasm and dedication necessary to sustain political majority.
3. The great Republican mistake was the belief that you could ignore everyone but your base. The great Democratic mistake was, and continues to be, the belief that you can ignore your base. All those enthusiastic young people who spent their days sleeping on floors and knocking on doors will not show up if they do not believe in you. Failing to vote funds for closing Gitmo, failure of courage on same sex issues (at a time when the states are showing considerable ferment), failure to take bold action on Wall St., all whittle away at the core base you absolutely need to win elections.
Mind you, I see considerable action by both Congress and the Obama Administration to follow through on campaign pledges. But I also see a lot of unnecessary dissing of the base on core issues for fear of looking "too partisan." There is a balance between where Republicans are and where Dems traditionally have been. Hopefully, the Ds will find that sweet spot before it is too late.