It isn't impossible to imagine a scenario where Hillary wins the Democrat nomination. She will be permanently behind in the delegate count, as many have pointed out. It may not matter - neither her nor Obama will be able to make it to 2025 delegates on their own. That is the number required to lock the nomination. The super delegates would have to call it in such circumstances. If Hillary had ended the primary season on a winning streak, its not hard to imagine them deciding in her favor, even if Obama had a very slight overall delegate lead.
This would almost certainly cause a civil war within the Democratic Party. It is much easier to imagine a John McCain victory after such a tumultuous outcome. I for one would not hesitate to vote for McCain if forced to choose between McCain or Hillary. This may be the third virtually unlosable election in eight years that the Democrats are well on their way to losing. It almost makes me pity them.