yes, you can
i got 5 offers, but my visa statement is for University of Windsor.
When i landed on Vancouver, gave the immigration officer my visa, passport, school offer, and tuition statement, complain everything.
[make sure that the tuition fee of both universities are nearly the same]
Tell the officer:
I have got Windsor's admission offer first and used it to apply for my visa, but the problem is, after I sent out my visa application, Carleton also sent me the offer. Compare both universities, I prefer the Carleton. I wonder if any possiblity that i can change my statement from Windsor to Carleton.