depends on your own situation. If you haven't contated any professor who may hire you or the dept you apply admits student by a committe. You may be filtered in the first turn by secretary. BUT, If you have found a professor who is interested in you, you are fine.
Of course, rank of the dept is also important. You can get admitted by a third tier school without finacial aid easily.
BTW, my overal gpa is less than 3 and GRE verbel is terrible and it was taken in 2002. I got admitted without assistantship after I did almost 9 months work in a prof's lab.