I wouldn't bother with alums, unless they've donated enough to build a new library or whatever. It probably won't make a difference, and I wouldn't be surprised if legacy status itself in the next few years became much less important (if I remember correctly, Harvard undergrad has decreased it's emphasis on legacy status in favor of getting a more diverse student body, and I don't think it's improbable that other schools may follow).
However, if you've got solid connections with deans or professors (profs in the law school, anyway, or involved in the ls in some way...a prof of history isn't going to be much use) can't hurt, and as they have more of an idea of what would make a good law student, a call or note from them might be a small boost to your app. It'll still probably come down to the strength of your application, though, and from what I've heard about your numbers, work, education, etc, lexy, I doubt you'll have a problem.
partly an ethical question, partly just wondering if any of you are doing this or think it makes a difference--
asking people with connections at various schools to put in a phone call on your behalf? e.g. profs or employers or friends with big ties to schools, endowed chairs, alums who give a lot of money...do you say hey, i'm dying to go to X, aren't you still tight with some faculty/deans there?