Yes, you can, but it will need to be a whopper. I know of at least one instance when a passenger was required to put $500 per person down on his shipboard account - to start with - since he was using cash or travelers checks instead of a credit card. Call your T.A. or cruise line to be sure of the amount before you go - you don't want to be caught short!
Thanks alot 500.00 per person seems alot its just 2 of us. I hope not we were only wanting to spend 500.00 for bioth of us, im going to call t/a Thanks Ryan