Contrary to popular belief, there is no such thing as a pre-law major. Students majoring in biology, sociology, and yes, political science, among others, all attend law school with fairly equal chances of admission. Law schools do not prefer one major over another.
Law students come from a variety of backgrounds.
Their majors range from science, engineering, philosophy, political science, english to much, much more. Choose a major that interests you. No matter what your major, work hard and earn good grades. Clearly you should strive to earn impressive grades while taking challenging courses. Your transcript is important.