Aglages pretty much got it there. When I graduated (2010), we had 3 clots per year for nursing and it was to the Vanderbilt program.
There is a liaison at USAFA in the bio dept (usually) who can provide you with course requirements once you are there. Bio or Biochem will generally hit all the course requirements. It isn't terribly competitive - but that tends to be because not enough people fill the requirements (courses, GPA, tests). If you qualify, you stand a good shot at getting it.