That nonsense applies to all denominations.
This is about voter data, not whether voters are rigidly devoted and pure to whatever church they are members of.
The Catholic category is much more rigid and exclusive than the Protestant category, “Catholic” means members of that single denomination, of that single teaching, single culture, of people actually baptized into that church, and who still consider themselves as members of that church, which they are.
To be counted as “Protestant” they merely have to identify as Christian and not Catholic. They don’t have have ever to belonged to any church, or even be baptized, or they can belong to any range of churches or denominations, Black, Episcopalian, homosexual, Obama’s church, Southern Baptist, Lutherans, or whatever.
No, it is about data manipulation to prove a preconceived point, exactly what like the Global Warming crowd does. A more accurate analysis would categorize this as "more liars vote for Obama". Meanwhile, your effort to blame Catholics for all of the woes of the country, in the grand tradition of the Know-Nothings, is meaningless.