Maybe it's due to the early wave of white flight which began shortly after WWII
In which case we should see a huge numerical increase of Eisenhower votes in Bucks and Montgomery counties.
Well, that's what happened.
Ike got 11k more votes than Dewey in Bucks and 30k mores votes in Montgomery.
I guess that solves one piece of the puzzle.
Not really, as 1952 had a huge surge in turnout too. Philly had an increase of more than 100,000 voters in 1952 and Stevenson's vote increase in Bucks and Montgomery too.
Yeah, it definitely seems like a substantial portion of voters in Philly were Roosevelt ‘44-Dewey ‘48 voters. Why, I have no idea.