Thanks for the replies so far, looks like it is about 50/50.
Here are a couple more photos, not the greatest quality as I didn't take much care in snapping them, but I can get more close-up shots tomorrow if it would help you identify.
It's our first time with chickens and this one is starting to show some differences between the other Orpingtons. She/he has more red underneath the throat than the other two and a bigger comb, at least at this point. They are about 5.5 months old now.
Just joined up, we are starting our own little chicken family shortly.
I was wondering if anyone had recommendations for breeders in the east valley? I think we are most interested in Buffs and Ameraucana at this point. I had a number for a place that I got from Higley Feed, but I have lost it...