It's probably too late to do anything about it.
1- Barack Obama: His weak leadership, his attempts to please everyone, to be like Lincoln and his lies and betrayals, selling out the public option, fighting against auditing the FED, allowing abuses of the constitution Bush initiated-- these added up to major reason the Dems will lose in November. Obama had a chance to strengthen reform. Instead, he sabotaged and weakened it. He appointed DLC right wing leaning people to his administration, Banksters who were part of the problem to financial posts and was weak and passive with the military, letting them tell him what to do, failing to take the responsibility as Commander in Chief to make the tough choices.
2- The Blue Dogs in the senate: Max Baucus, Ben Nelson, Mary Landrieu, Blanche Lincoln, and, not a dem but working with them-- Joe Lieberman-- they all stopped the congress from getting a lot done. They blocked strong regulations, kow-towed to big corporations and flat sold out to big donor industries. For a short time, the Democrats had a 60 vote, filibuster-proof majority. This handful of backstabbing traitors screwed us all. Even if the Democrats retain the senate, it will be with the help of these losers. You might as well put them on the Republican side of the aisle come January 2011. And I wouldn't be surprised if at least one of them broke with the Democrats and changed party.
3-Rahm Emanuel: he played a major role, as head of the DCCC, recruiting bluedog dems to fund and run against strong, viable progressive Democratic primary candidates. That pack of worthless bluedogs in the house-- blame Rahm Emanuel for a lot of them, and for their strength. And then, as Obama's chief of staff, he's been there to root for the right wing angle, the corporate angle, to cut deals with corporations that stabbed constituents who trusted Obama in the back. He worked for Obama then, but he could have advised him to be a better president instead of one who, so far, will go down in history as a failure.
5-Filibuster-averse Democrats: They should have filibustered obvious right wing extremist Supreme court nominees Roberts and Alito. Forcing more moderate nominees might have prevented Citizens United from securing their victory, which will be devastating in November.
There's no doubt in my mind that the biggest cause was Barack Obama. His weak support and passive engagement in the legislative process was bad, very bad for the Democrats. His abject failure to be a strong, decisive leader in the face of the Gulf BP oil disaster pretty much insured that he would go down in history as a one term president. That doesn't have to be the case. He could redeem himself in many ways. But so far, holding hope that Obama would do the right thing when it counts has been a futile effort. Yes, he's made a few things happen. But for the most part, the legislation he's been involved in getting through has been weak and afflicted with loopholes and give-aways for big corporations. On the other hand, he's been far worse than Bush on some issues, like whistleblowers.
Unless a miracle happens and the Democrats morph into something very different, unless Obama wakes up from he nightmare he's caused all we progressives to be living in, the Democrats will probably lose the house and by 2012, perhaps the senate and probably the White House, because they will be too inflexible and blind to realize that Obama doesn't have a chance.
There are more to blame. I invite you commenters to add to the list.
Meanwhile, we had best be bracing for a few years, maybe six or more, of right wing hell... again... and facing the reality that the USA is really the CSA-- the Corporate States of America.