In some ways, the 1920s was a time much like today, one in which there were conservative and liberal sectors of the United States and something of a culture war going on between the two.
The cities of the United States tended to be culturally liberal during this time. This was seen in the "Jazz Age" culture of the cities, especially in the new atttitudes towards women's proper behavior (the flappers) and towards sex.
At the same time, however, there was a strong conservative backlash, especially in the country. This was an era when the KKK grew strong by pushing for a more traditionally "American" set of values. It was an anti-Catholic, anti-immigrant group that was very conservative in its desire to protect a pure "Americanism."
So, much like today, you had a liberal trend in urban areas opposed to a very conservative, traditionalist strain of politics, especially in more rural areas.