The "same can of gas" may have had some crud floating on the bottom.
How old was it?

The gas may have been a couple of months old. But it was in my garage and the container was closed.

Just to test whether this is actually a "gas problem" or not.
Pour a couple of spoonfuls of gasoline into the carburetor.
If the engine tries to start and run on that gas........it might be a problem in the fuel system.
But, if the engine still does not try to run, you may have worse problems.
Make sure the engine produces good and consistent spark while it is being cranked. You may need someone else to sit in the seat and crank while you watch the spark.
If you are not getting good, crisp, continuous spark, the seat switch may have developed a problem.
If you are getting good spark, you will need to move on to checking for compression problems.
Which one of those Craftsman tractors did you buy? and does it have a brand name engine in it?

It is a Craftsman Model 917.28713 and it has a Briggs and Stratton 20 HP engine in it.

My main concern right now is how to get it to move even without starting the engine. It is sitting in my drive way and I need to get it to the shed before it rains again.

This post was edited by jebreynolds on Wed, Aug 6, 14 at 10:21

jebreyreynolds - according to the model number of the machine you have posted, you have a standard gear drive model. Simply move the gearshift lever to the neutral position, raise the mower deck to a high position, release the park brake (if on) and push the tractor ( with engine off) by hand to the shed.

I did all that but it will still not move. How can I tell if the parking brake is engaged? I did not purposely pull it, but I can not think of another reason that the mower will not move.

if your gear shift is indeed in neutral, there is only one other thinf that can stop the tractor from moving - a frozen-up park brake mechanism. This usuallu consists of a disc mounted outside of the tranny case gripped by a caliper linked back to your bake pedal.
Normally, the caliper is spring released and the disc is not gripped, allowing free tranny movement. However, If you left your park brake on when the the engine stopped and the mower sat out in the weather, the mechanism may have frozen in the applied position.
this device is located on the outer tranny case just ahead of of the r/h rear wheel - up under the tractor frame.
A few shots of rattlecan brake pad cleaner to the caliper assy (avail from the auto parts store) and some manipulation of the park brake linkage will loosen the assembly - the tractor should freewheel normally.
Also suggest you go to sears parts (as I did) - take that model number 917.28713 - add the missing 0 to the end - and download a free copy of the owners manual and the various parts lists diagrams for your tractor - take the time to read up and become familiar with what make that mower tick. Good luck.

Thanks for the suggestions. I should have some time this weekend to try all that out. Hopefully it will work.