Sure, it could be the ignition switch; but it wouldn't be my first choice. First things first. I would double check the battery voltage across the terminals, but also from the starter solenoid to the engine. I always wiggle the cables to see if they are stiff, or corroded, or loose.
I would then test for voltage on the key switch contacts before you do anything else, and then, if voltage is present, check that you get voltage on the other wires when the key turns. Did you check the voltage at the fuse box, and across the fuses?
I tend to reduce these things to the basics, and wire trace. If it were me, if none of the above work, I would start at the fuel solenoid, or starter solenoid, and work back.
All the best,
Peter