OK, I put a PLASTIC container up on the roll bar with duct tape and filled it with gas. Put a nozzle from my aquarium supplies in the bottom. Ran a hose directly to the carb, bypassing the fuel pump and fuel filter. With gravity as the "pump" I tried to start it and it caught and ran after 2 cranks! I visually verified that the fuel pump was pumping (spurting gas out) and caught the gas in a container. I let it warm up a bit, shut it off, and put everything back as it should be. It then started right up (and has several times over a week, since)! So it's back to normal and I have no idea why it wouldn't start.