I would not be at all comfortable with that scenario. The potential point of failure will not likely be the cruise line, it will be the airline. I assume you are flying with a carry on and don't need to claim baggage.
One bit of weather, or congestion at an airport, a mechanical problem and you are hosed.
Do yourself a favor and call the airline to see if you can get an earlier flight. It isn't even worth taking the chance, even if the flight is free. Better to always fly in the day before if you can swing it. I remember one trip to Miami and our cab kept dieing. We were sitting in the middle of the street and it delayed our arrival substantially. You need to leave yourself a little more breathing room.