The amount of aid available from the US colleges and universities varies from zero at some institutions to several million dollars at others. The hard reality is that most colleges do not have enough financial aid to meet the needs of all their students. Here is the area in which it will pay for you to do a bit of research into the aid policies of the school you are considering.
Note- If you do not need financial aid, your chances for admissions may be improved. However, if you really will need aid in order to attend college, you should apply for it.