the stats I saw might be in one of those reports
http://www.cna.org/my_search/google?my_gcs="marine corps officers"
http://www.cna.org/my_search/google?my_gcs="marine corps officers"
I saw a table from a CNA report about USMC ROTC officer accessions.
the largest top five are Citadel, Texas A&M, VMI, Villanova and Notre Dame. that was from the early 2000s.
but any ROTC unit with a large Semper Fi group. Also with a MECEP contingent.