Yes, it is possible, but before you do anything, contact the ROO or PMS at the #1 college and see if the Cadre can wield any influence over admissions. Mileage varies.
Follow their advice first.
I believe that either way, you need to accept the scholarship, for at least the #2 school. Based on the outcome of #1's admissions, you can then ask Cadet Command to switch the school choice.