You might be able to do that, it will be close. You may be more rushed than you want to be, you will need to be on the way by 5:30 to allow for traffic, etc. You will want to be at the airport 1.5 to 2 hours before your flight (maybe 2-2.5 hours as you are going to Toronto).
It's about an hour and 30 minutes from WDW to the Tampa airport and if you have a rental, allow time to drop off the car and get to the security lines..