Why do Christians become Christians?

[SteveII]

Has anyone ever "come to Jesus" without having heard about him and the stories surrounding him for long periods?

I think not. The seeping in of ideas surrounding you is not surprising. People independently describing "meeting" Jesus, while isolated from any mention of him, would be surprising.

In short, people are very susceptible to the appeal to popularity fallacy. If many people seem to believe it, it appears a reasonable belief.

Regarding an appeal to popularity--perhaps for some this has an effect. However, in many families and locals of the world, it would be decidedly unpopular to become a Christian. It seems you are so convinced there must be extenuating circumstances an not the message itself to explain why Christianity is doing so well.