PA had two statewide races. Tom Corbett won by ten percent. Toomey won by two. Not everyone votes straight ticket.
But that being said, doesn't it seem odd that 1/4 (110,000) who voted in Clark county voted ONLY for the House seat but did not vote for the Senate seat? In this case, if you can stuff the ballot box in the Senate race, or eliminate 110,000 votes, you can determine the outcome of the Senate seat. Especially in such a hotly contested race. This is far more difficult to do county by county-but not if you control 2 or 3 counties. I'm not a seasoned pollster but I would think, given the percentage of unpopularity with Harry Reid in the other counties, there would not have been such a wide swing for Reid in Clark county. What happened to these votes?
This is a statistical anomaly.