Mike, do you have a test light?
If so, test the small "ignitor" wire, usually a blade connector. Have someone turn the ignition to the start position. If it lights up, you have reference from the ignition. Switch, wiring, and relay are proven ok at that point. Check for 12V at big wire. Only other thing could be a huge voltage drop between the battery and starter, or the starter.
It is possible that the starter solenoid is really jammed up and may not click, but not good to assume.