Hello Aspirant,
As you have not mentioned your category so it is little bit difficult to guide you accurately. Although with 66% marks in class 12th your chances of getting B.Com program in any college of Delhi University are negligible as cutoffs are usually higher around 90% to 95% for General category candidates even for reservation categories it does not goes this much down.
However, if luck favours you might get lower ranked off campus colleges in special round cutoffs. I would suggest you to keep some other universities as back-up.
You can get more details on cut-off for DU from the link given below :-
https://university.careers360.com/articles/du-cutoff
I hope this information cleared your doubts.
Good Luck!!
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