MSNBC and Fox News are both reporting that Hillary Clinton will win Pennsylvania's Democratic primary.

The margin of victory, however, will likely make all the difference. A narrow win for Clinton may end up looking like a moral victory for Barack Obama. Indeed, there are some reports this evening that the Obama campaign's strategy of late was to force Clinton to spend heavily for a single-digit victory, which would leave her with limited resources for the remaining contests.

Clinton told reporters earlier, "A win is a win." If she ends up winning by a small margin, expect to hear that phrase a lot tomorrow morning.

Update: ABC and CBS have also said Clinton will win Pennsylvania. CNN's Wolf Blitzer said the race is "very competitive."