How do we Evangelize to Catholics and Other Denominations?

Full question: We tend to evangelize only to those who don't know Jesus at all. I think I am just curious how important it is to evangelize to Catholics, or those who aren't exactly believing everything theologically "correct". I understand Mormons believe very different things about God and Jesus and can see why we would need to spread the gospel to them. But what about people who are believing Mary was sinless or that we have to work for our faith? How do we go about this? Links Mentioned: Reasoning From The Scriptures With The Catholics by Ron Rhodes To read the full show notes, click here.