An interesting observation from Noam Scheiber in response to Clinton's latest assault:

Strange how the Clinton approach to strengthening the Democratic Party is remarkably similar to the GOP's approach to strengthening the Democratic Party.

At this point, it is possible that the biggest hurdle Hillary would face in seizing the nomination is not her deficit in delegates, but the perception that she has become another arm of the Vast Right-Wing Conspiracy. And rather than McCain facing two opponents at once, it's more like Hillary's playing steady QB--which is clearly leading to some resentment on the left.