"Hard statistical studies repeatedly find that there is no better way to predict ethnocentrism than to measure political conservatism."
[...]
"In 1920s America, conservatives lobbied for lower immigration quotas for Irish, Italians, Jews, and Poles, whom they called 'inferior races.' Ninety years later, the immigrants were different and the politicians shied away from overt prejudice, but conservatives were still the group most opposed to immigration."
-- Avi Tuschman, Our Political Nature (Prometheus Books, 2013), excerpted at Alternet