Query: What party dominated until the mid-20th century
Context: From the American Civil War until the mid-20th century, Philadelphia was a bastion of the Republican Party, which arose from the staunch pro-Northern views of Philadelphia residents during and after the war (Philadelphia was chosen as the host city for the first Republican National Convention in 1856). After the Great Depression, Democratic registrations increased, but the city was not carried by Democrat Franklin D. Roosevelt in his landslide victory of 1932 (in which Pennsylvania was one of the few states won by Republican Herbert Hoover).