Hi Karthik,
Thanks for writing in. While part-time programs tend to be a little less stringent on GMAT requirements than their full-time counterparts, I have concerns that a 640 GMAT may not be enough at Haas, UCLA and borderline USC. If you can get that up to about a 670-680 I would rate you competitive. You are likely already competitive for Santa Clara.
Best of luck,
Daniel Richards
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