Hello there Danzig,
It looks like you have some fantastic stuff in your profile - Being valedictorian, plus your very prestigious sounding work experience. Good governement work is one of the best things you can apply to B-school to, esp. if you have some sort of dream to change the future. But still, the schools you are aiming for will be TOUGH with a 680. Not impossible! But you will be at a big disadvantage in comparison to others (they might just ask themselves: "Well why didn't he just retake?")
Right now, I don't really have enough detail about exactly what you do, where you are from, what your goals are to advise you further, buuuut feel free to drop us a line, and I or one of my consultants will give you a more precise evaluation, and for that I'd suggest you fill out our form (which asks all the right questions) for a free consultation:http://admissionado.com/mba/free-consultation/
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