It seems some of the more expensive private schools are easier to get into. Even ones that are very well respected.
For instance, USC says on their APTA weblisting:
"In the past year, 296 persons applied, and from that number 95 students were enrolled."
http://apps.apta.org/Custom/wstemplate.cfm?cfml=accreditedschools/Index.cfm&cfmltitle=Accredited PT and PTA Programs§ion=&process=2&ProgramID=E96608E2%2DF302%2D4C64%2D8F6B%2D6DB4BCFC78FD
That's 32% of applicants that eventually ENROLLED. So, the number of applicants who were accepted must be considerably higher than that.
For Washington University, on APTA, they say:
"75% of qualified applicants are admitted to the program (3-year average)."
http://apps.apta.org/Custom/wstemplate.cfm?cfml=accreditedschools/Index.cfm&cfmltitle=Accredited PT and PTA Programs§ion=&process=2&ProgramID=ED303BFB%2DECF5%2D4645%2DA06A%2DDCD023EB2AA2
I remember seeing Northwestern's profile on that same site showing an acceptance rate of 40% or so, but that information is no longer there. But on PTCAS they list their average GRE score as 1066 which is very average.
http://www.ptcas.org/Northwestern.html
Obviously, if your stats aren't great, do what you can to maximize your application.
But also, do some research on apta.org and ptcas.org and school websites.
Some schools have very high cut-offs for GPA and GRE scores, and accept a low percentage of applicants.
But, some really, really good programs seem to be accepting a high percentage of applicants. And as evidenced by the GPA/GRE forum on here, some applicants with average stats are getting into these really, really good programs.
Good luck!