Well, there are multiple reasons. Clay Risen, author of American Whiskey, Bourbon & Rye: A Guide to the Nation's Favorite Spirit touches on a few of them:

“You saw a lot of bartenders going back to pre-Prohibition recipes, finding a lot of things that were rye-driven. And consumers jumped at it. So, that was one thing. And then, I think the other is that there's a lot of curiosity out there these days. People want to try different whiskeys. There's no brand loyalty, there's no style loyalty. So, something like rye comes along and people say, 'Oh, that sounds great. I want to try something new.'"

Read the entire CBS News feature on the resurgence of rye.