One caveat: you might decide at some point not to go to law school. Therefore, you should consider a major in a field that can get you a job out of undergrad. A hard science, engineering, business, or something like that are the safest undergrad majors for the rest of your life.
If you like it, try philosophy. Beware, though, that if you change your mind about law school, you'll basically be broke and unemployed. If you're sure about the law school route, though, a strong background in analytic philosophy is great preparation.
Make sure you have as high a GPA as possible.
Pre-law is a complete joke major, and I don't even know if I would accept someone with a pre-law degree if I was in law school admissions. That's a ridiculous thing to say. I'm glad you're not on an admissions committee. You can't judge an applicant soley on their major. I'd venture to guess that the average person only retains a small percentage of the knowledge they gained anyway. What about the pre-law applicant who reads books all the time and the political science applicant who instead watches reality shows all the time? To suggest that pre-law people cannot be as good is simply wrong.