In the scene where Hazel confronts Adam about the rejection she received from Constitution Hall, Adam says, 'they did that to Marian Anderson 5-years ago'. Marian Anderson's rejection occurred in 1939, which would make 1944 as the time-frame for the scene. Powell did not become a congressman until January 1945.
During the montage at one hour in, the announcer says "President Eisenhower leads the first Republican Administration in 24 years." Eisenhower was elected in 1952, 20 years after Herbert Hoover was defeated; it was 24 years after Hoover was elected and inaugurated.