Interesting. Republicans will control the House, but more Americans voted for the Democratic candidates.
If you overlay the above map with a Pennsylvania County map, you'll see that those blue areas correspond quite nicely to the areas where Obama had a majority. So even though Democrats enjoy a one million voter edge, Republicans will hold the vast majority of the state's 20 seats.
This is the effect of drawing congressional districts in order to maximize the number of seats. If you have a city with lots of Democrats, and say, the state is controlled by Republicans after a census, you'll try to group as many of those Democrats into as few districts as possible. Conversely, if the Democrats control the legislature, they'll try and split that city population between as many districts as possible, while maintaining safe majorities, and maximizing their seats.
There should be a better way, but whenever some sort of district boundry boundry plan attempted to reflect reality, its been opposed by one party, the other, or both..