Kammala wannan jumla: Philadelphia ya kasance mai karfi na Jam'iyyar Republican daga yakin basasar Amurka har zuwa tsakiyar shekarun 1930. Birnin ya karbi bakuncin taron kasa na Republican na farko a
Shekara ta 1856. Rijistar Democrat ya karu bayan Babban Mawuyacin hali; duk da haka, ba a gudanar da birnin ba ta Democrat Franklin D. Roosevelt a nasarar da ya yi a shekarar 1932 kamar yadda Pennsylvania ta kasance daya daga cikin jihohi shida da Republican Herbert Hoover ya lashe. Masu jefa kuri'a sun tashi daga 600,000 a 1932 zuwa kusan 900,000 a 1936 kuma Roosevelt ya lashe Philadelphia tare da fiye da 60% na kuri'un. Garin ya zabi 'yan Democrat a duk zaben shugaban kasa tun daga 1936. A shekara ta 2008, dan Democrat Barack Obama ya zana kashi 83% na kuri'un birnin. Nasarar Obama ta kasance mafi girma a shekara ta 2012, inda ya kama kashi 85% na kuri'un. A shekarar 2016, Hillary Clinton 'yar Democrat ta lashe kashi 82% na kuri'un.