It's totally true, when you account for Jews, the White Christian is clearly the most under-represented in colleges. Take Yale for example. 52% of Yale is White. Yale University - CollegeData College Profile But 28% of Yale is Jewish. 2015 Top 60 Schools by Jewish Student Population So, actually about 24% of Yale is White Christian, and 28% White Jewish. I'm only strictly speaking of a "White Christian background" when you account for Agnostics, and Atheists obviously the number goes down even more. But, that means that White Christians are very well under-represented in Yale.