Thank you, single-serving internet friend!
Clever. How's that working out for you?
Grand Rapids MI
That's in Kent County. Trump won 48.3% of the vote, Clinton won 45.2%, and Average Home Value is $169,800
Having live there for a decade, Kansas City is actually pretty decent if you're in the city core (e.g. look at the Brookside neighborhood in Kansas City, Missouri). MO is fairly red as a state but KC (and STL) are the bastions of blue.
The main issue with KC is, if you have or plan to have kids, the public schools are not very good at all, so you're forced to private school if you care about education quality. There's plenty of good suburbs choices too (Liberty, Lee's Summit, and Overland Park (KS) come to mind) with great schools + affordable. But even those get red very fast, and I personally loathe the suburbs.
Philly was a huge surprise for me too, I think it's the county as a whole and a large swath of low-priced housing. I'm guessing the nice areas of the city are extremely expensive.
You might expand your search to Chattanooga, TN; Fort Collins, CO; Bellingham, WA; Boise, ID; Missoula, MT. Those are all relatively affordable still with a good progressive culture that's rapidly growing.