It's the population density that causes them to be majority libtards. That's true of city Asian-Americans and everybody else that lives mostly in concrete and steel communes.
Except that you are wrong, I am from a big city, many of us are, Evangelicals live in big cities, lots of conservatives do, and it does not explain 150 years and more, of Jewish voting.
Care to explain the 1920 Jewish vote, or 1980, or why other groups that are not liberal can be big city people without voting liberal, or why some people seek to move to liberal centers, or away from them, or why Austin is so much more liberal than Houston?
According to you, people don’t have politics, they are just reacting to population density.