In top colleges like SRCC, Hindu College, St. Stephens, Ramjas College, Hansraj etc, chances are low as these colleges have cut offs in the 96%-99% range. In colleges like Acharya Narendra Dev College, Aryabhatta College, Deshbandhu college, Dr. Bhimrao Ambedkar College, Dyal Singh College, Motilal Nehru College, P. G. D. A. V college, Rajdhani college, Shivaji College, Shyam Lal College, Sri Aurobindo College (evening). Do keep an eye on cut off of each rounds, in the later rounds the cut off goes lower.
I could not understand your point about merit base. If you could explain it in the comments below, I can help you better.
Hope this helped. Good luck.
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