Da Vinci Code’s last secret: how did it succeed?

An Anonymous Patron writes Da Vinci Code’s last secret: how did it succeed? It may be the last mystery left about “The Da Vinci Code” — how did a work by a near unknown author and sneered at by some of literature’s leading lights become one of the best-selling novels of all time?
 
“The book challenges the familiar story of Jesus’s life but it is also challenges ideas that for a vast number of Americans are a familiar part of their faith and people enjoy toying with things that are subversive.””