As I'm sure you know, you are targetting three of the most difficult schools out there! These are very popular (and highly ranked) business schools and the competition is fierce. It is difficult for me to give you a complete answer based only on the objective data provided as much of the process is subjective (LORs and essays), but, I think you have a tough road ahead. While Duke is a great school, your GPA is on the lower side and your GMAT may also be a little low for these schools. Because you are a more recent graduate, your grades matter more now than they would if you applied in another year or two. I think you could improve your chances if you waited (this would enable you to bulk up your resume and LORs and also have a bit more distance from your GPA).

If you want to apply for next year, I think you'd have a great shot at a top-20 school (but I'd broaden your search outside of the three that you are currently targetting!).

Hope this helps. Good luck!