What are you trying to prove? This is nothing new, as there are always tares among the wheat, and while the 21% who voted liberal is grievous - and consider that it aparently included blacks and Latino evangelicals (you forgot to even give a source: http://www.pewforum.org/Politics-and-Elections/How-the-Faithful-Voted-2012-Preliminary-Exit-Poll-Analysis.aspx) - and you are attacking the most conservative Christian group there is.
Take a look here: http://www.peacebyjesus.com/RC-Stats_vs._Evang.html
Some RCs are eager to blame the 21% of evangelicals who voted like 50% of Catholics.
An improvement upon that 50% of Catholics would have delivered Ohio and Pennsylvania.
And what benefit did Paul Ryan provide? None that I see
Oh no, it’s the Evangelicals’ fault, though. A ticket with a Mormon and a Catholic, Evangelicals vote for that ticket higher on a percentage basis than any of them, Mormons included.
Ridiculous. It’s either a dire lack of math skills on the part of those making these claims, or as you say, a desire to deflect blame from some other group.
At least they’re not very good liars and propagandists, not yet anyway.