What's even weirder about that is that the Republican won by 11 points with that map. We like to think of there being increased urbanization in recent decades, but even sweeping the entire countryside and suburbs wasn't enough to make the Democrat competitive against a Republican winning Erie, Pittsburgh, Philadelphia, and the Wyoming Valley.
PA was a very Republican state is this era (with Hoover even winning PA in 1932) but as with one party states there were two parties within the party, the machine and the remnants of the Bull Moose party led by Gov Gifford Pinchot. Pinchot lost the Sen primary in 1926 to the head of the Philly machine, William Vare. Pinchot's base was rural PA and he hated Vare and in fact prevented Vare from ever being seated in the Senate due to accusation of electoral fraud. The D candidate was from rural PA (Tioga Co) and was able to do as well with it as could be expected.
It should be noted that Vare won the six most populous counties in the state, Philly and Alleghany of course, but the next four are quite different from today--Luzerne, Lackawanna, Schulkill, and Lancaster.
In 1930, Pinchot ran again for Gov and narrowly won a 3pt victory with his map looking this
Philly went from 80-19 Vare in 1926 to 74-26 for Pinchot's D opponent in 1930
