Jonathan Chait and I don't agree on many things. But this piece on the primary is masterful:

The morning after Tuesday's primaries, Hillary Clinton's campaign released a memo titled "The Path to the Presidency." I eagerly dug into the paper, figuring it would explain how Clinton would obtain the Democratic nomination despite an enormous deficit in delegates. Instead, the memo offered a series of arguments as to why Clinton should run against John McCain--i.e., "Hillary is seen as the one who can get the job done"--but nothing about how she actually could. Is she planning a third-party run? Does she think Obama is going to die? The memo does not say.

The reason it doesn't say is that Clinton's path to the nomination is pretty repulsive. She isn't going to win at the polls. Barack Obama has a lead of 144 pledged delegates. That may not sound like a lot in a 4,000-delegate race, but it is. Clinton's Ohio win reduced that total by only nine. She would need 15 more Ohios to pull even with Obama. She isn't going to do much to dent, let alone eliminate, his lead.

That means, as we all have grown tired of hearing, that she would need to win with superdelegates. But, with most superdelegates already committed, Clinton would need to capture the remaining ones by a margin of better than two to one. And superdelegates are going to be extremely reluctant to overturn an elected delegate lead the size of Obama's. The only way to lessen that reluctance would be to destroy Obama's general election viability, so that superdelegates had no choice but to hand the nomination to her. Hence her flurry of attacks, her oddly qualified response as to whether Obama is a Muslim ("not as far as I know"), her repeated suggestions that John McCain is more qualified.