I’m not making it up. 40% is a ballpark figure, which is plausible on the face of it. Catholics were about 25% of the population in 1940, and concentrated in the urban and industrial areas of Midwest and Northeast. They were also less educated, and so in an army where a guy who read “Life” Magazine was thought to be an intellectual, people drafted from such places would tend to end up in combat arms. Southerners were also over-represented. But if you don’t like deductions, that is your problem.
You can’t just keep making up such fake facts.
Now show us the data for Catholic veteran voting in presidential elections.