Michelle Cottle has a superior article at The New Republic on what happened to Hillary Clinton's campaign. It is told by "the high-level advisors, staffers, fundraisers, and on-the-ground organizers who lived it."

It is not a pretty picture.

Evidently, part of the problem was that Clinton just didn't want it bad enough:

Bottom line: I just don't think she was hungry enough for it in the beginning. It wasn't really until the ten-in-a-row loss that she started doing stuff like Saturday Night Live and Jon Stewart. In the beginning, it was hard to get her to do those things. Early in the campaign, she spent much more time in the Senate than the campaign would have liked. It took the threat of a real loss to get her hungry enough for it. But time was lost. If you ask the Iowa folks, I'm sure they would tell you she wasn't there enough."

"Clearly [Obama] was a phenomenon. He was tapping something really different than anyone had ever seen before. ... Months and months before Iowa, he was getting record crowds. I just think they should have really gone after him back in the summer and in the fall. I know it would have been a difficult decision to make back then. She's the leader of the party, the standard bearer, the big dog. Everyone thinks she's gonna win and walk away with it. Why go picking on Barack Obama? But that's just something the campaign should have done sooner."

"We didn't lay a serious glove on him until the fall. We tried to a little bit, but we weren't successful. We did silly stuff, like talk about David Geffen. It wasn't the substantive contrast we needed to make."