[Patrick Appel] Ross makes a good point:

[Clinton's] been campaigning as if the Democratic primaries were winner-take-all, essentially giving up on the run of states where Obama looked likely to win (thus allowing him to rack up huge margins of victory, and overtake her in the delegate count) while doubling down on the later states where she's ahead. It's the Giuliani strategy all over again, in a sense - except that the Giuliani strategy at least made sense in theory, because it promised to deliver Rudy an enormous delegate haul in winner-take-all states like Florida, New York, New Jersey and Connecticut. (A haul that McCain eventually claimed, as it happens.) Whereas even if Hillary's strategy works, it won't really work, since she'd need enormous, unrealistic margins in Texas and Ohio to make up the ground she lost by essentially ceding two weeks worth of contests to Obama.