I believe the Ivy League and the other leading law schools (Stanford, NYU, Berkeley) consider other things, mainly your experience, your acquired expertise if any, your career path for the immediate future (Yale, Harvard and Columbia have a bias for teaching and government service). If you top your JD class, they will surely look at your application. If you are the editor of the law journal, you'll have a good chance of getting in. Volunteer work for public interest law also helps. Once you get in, you can always study other subjects (especially at Columbia, which, I believe is most liberal among the best of the best, when it comes to courses and seminars). Yale, Harvard, Stanford, Chicago and NYU are all very strict about the courses of their LLM students. Finally, yes, your standing in your pre-law matters in the LLM admissions. But you can set off whatever you lacked their by doing excellently in the JD.