I know that in today's world most Christians are going to be conservative, but that doesn't mean that liberal Christians are an impossibility. As long as you accept that Jesus died on the Cross for our sins you are a Christian.
Granted, and I know a few in my own parish - though I have a hard time understanding how they can support pro-abortion politicians and still be Christian.
This particular author, however, is so full of hatred that I have to question whether he is in fact a Christian.
By their fruit you shall know them.