I'm a person that grew up without a dad and went through the same "daddy" question. There are severe consequences that children go through when both parents are not in there life. You said she doesn't have a dad and that's untrue. She does. He may not be a part of her life but she does indeed have a dad. Have you made any efforts to talk to him so he can become a part of her life?
This question is not going to go away for her. Moms often have a fear of the child being taken away by the father, just as my mom did, which kept him from seeing me. I grew up to resent that and your daughter may grow up to resent it as well. You may think lowly of the man now, but obviously you didn't just a few years ago because you created a child with him.
If I were you I would first try to contact him and see about getting him to become a part of her life. She needs that. If he outright refuses after having been given the chance, then I would talk to her about how daddy lives a ways away and can't yet be a part of her life. This is why making wise choices are so important to parents. I don't want to sound harsh but I was where she is now. I grew up with the same thing and I guarantee it will bother her for the rest of her life. There is no way to sugar coat it. You need to look past your own biases about him and see that her having a relationship with her father is not about you, it's about them two.
I'd just like to add on something about the severe consequences. Many women seem to think dads aren't needed in a child's life. That couldn't be farther from the truth. They are very much needed and necessary. There is a strong correlation between children being raised without fathers and later on getting involevd in crime, drug addiction, teenage pregnancy, dropping out of high school, etc. That's the statistics whether people like it or not or want to believe it or not. Some simple research will prove that.
Sometimes giving suppor to other mothers means telling them the truth, not just telling them what they want to hear. Support does not mean just being an idle listener and dishing out advice that goes down easy.
Furthermore, my mother was never my "hero" because she made us made us struggle growing up. If she wasn't selfish with her children and had allowed us to see our fathers we would have likely lived an easier life. Her poor decisions with men ended up causing me and my sisters problems despite her trying hard. My mom used to try the "I'm the mom and dad thing" but I just found that to be crazy and as an adult find it absurd. Moms and dads bring different things to a child's life and mom can't possibly replace what dad brings.