Are analyzed by the Washington Post. I think they missed something though:

In winning Tuesday’s primary in the key swing state of Wisconsin, Sen. Barack Obama drew support from tens of thousands of Republicans and independents. He pulled off the same feat in his landslide victory in the Virginia primary the week before, suggesting he could win the state in November.

The Republicans had already decided on our candidate by VA, so some of the crossover Republican voters could have been those who wanted to make sure Clinton was defeated in the primary to ensure that she didn’t face a weakened Republican candidate in the fall.
He will probably get a pretty decent turnout of Republicans in Texas and Ohio as they attempt to finish her off 🙂 End all doubt, vote her out!