It depends on who we are considering Catholic here. Do they have to be practicing or do they just have to identify as such? I can say with much certainty that your average white Catholic is no white evangelical. They're different breeds.
If you read the article (which is basically referring only to non-Hispanic white Catholics) it points how just how Republican they are now and in 2012 were in fact more Republican than white Protestants. The main reason for this though, which the article kind of glosses over quickly but people here have pointed out, is that the liberals are leaving Catholicism. Which shows that these "identification only" "Catholics" are actually not all that common anymore. After as the article mentions one third of those raised Catholic no longer identify as such.
