How did Wicked become such a popular Broadway play?

[DodgerGirl]

Ever since it opened on Broadway in the 2000's I never imagined how Wicked would develop a fanbase and become so popular. Is it because Wicked is a unique Broadway play or is it because it has a different type of The Wizard Of Oz story to it? Because I have seen Wicked on clothing merchandise and other things and the songs Defying Gravity and Popular have become popular songs. I didn't even know what Wicked was until my aunt watched the play on Youtube and she liked it. But I think the movie version has made Wicked even popular and I think it will break a world record for being the longest Broadway play ever second to Cats. But I think the movie version of Wicked will gain the Broadway play of Wicked an even bigger fanbase and more people will watch it