Looking at Juan Cole's blog Informed Comment I came across this graph showing the preferences of the four major religious groups (Islam, Judaism, Protestant, and Catholic) in the US for the top 5 Presidential candidates from the Institute for Social Policy and Understanding. The survey was conducted before Marco Rubio dropped out of the race. The focus of the survey was how Muslims compare to other religious groups with respect to the 2016 election. Predictably Muslims more strongly support Democrats Hillary Clinton and Bernie Sanders than the Republicans.
The one number that jumped out at me n the graph at the top was the group that most strongly supported Donald Trump. Donald Trump was supported by 4% of Muslims, 13% of Jews, 17% of Protestants and 28% of Catholics. This number seems worth investigating. Another graph in their report presented below shows that 47% of Protestants are more likely to identify as Republican compared to 34% of Catholics, 16% of Jews, and 6% of Muslims. This comes as exit polls in the primaries show Trump doing well among evangelical or born again Christians with Ted Cruz doing better in some states.