I don't think the word or a judgement of something being evil is the exclusive province of religion and has noticed many liberals and progressives using this word in the last 2-3 years as Republican and corporate behavior has degenerated rapidly, apparently with no remorse and much intention. Evil in the dictionary boils down to sth. that is:

!) morally bad, and

2) doing harm

and it also has definitions emphasizing extremely bad or wicked type behavior. We come into the world as very impressionable and our environment shapes a lot of our responses to certain situations and people, the world, etc. Good and evil are terms describing different sides of our behavior. It's interested to think 'how people view the world reflects their internal state'.

So Republicans may gravitate to the view all people are evil because that's closer to their behavioral state than the other side, good, which liberal folks 'believe in' possibly since we act more that way. I'm not imputing some generic difference or innate moral good, but a tendency, and it seems to be a strong tendency in what we see in the world today.

Of course, people who are hyprocritical and dishonest and highly religious naturally think of themselves in righteous terms, as very good or never in question (they can't face looking at their own selves). This is a psychological coping mechanism to be able to continue to do diverse, hypocritical things or have a view of oneself at odds with one's behavior....