Thats something thats confused me because I've heard them being called a race, but I always thought Judaism was a religion, and religion is something you choose to believe, not something that is passed down in your genes, so I would say that they aren't based on what I know, although I know that many people say they are.
I have a friend who is jewish, so I'll message him and if he gets back to me (he might be away at the moment) I'll let you know what he says :)