Why do Christians become Christians?

[Mr.wizard]

He means has anyone had a personal experience with Jesus, while never having come in contact with the message of Jesus or Christianity.

Rob specifically said "for long periods" and that is what I answered. 

If you are asking if the life and teachings of Jesus resonate with someone who has never heard anything about the life and teachings of Jesus, then no. 

Can God speak to someone's heart who will never hear the message?  I believe yes, but that interaction would be between God and that person and no one else is going to be able to comment/judge/deny on whether that is real or not.

Yes he wants to know how many people are finding Jesus without ever knowing anything about Christianity. If you are attending a Billy Graham event then you are being fed the Christian concepts and probably have some idea what Christianity is about, you are not coming to Jesus by any discovery of your own. 

What about all the people who have had a God talk to their heart and are not Christians, do you have any judgment about the reality of their god?