Did this recently happen, or has it happened the whole time you've had the Jeep?
Also, do you know if it's been re-wired?
Initial guess is a stripped wire somewhere or a bad connection (loose or barely hanging on) on the switch. If it was rewired at some point, could be that a wire is too short.
I have a feeling you're going to see the problem once you take a look inside...
The electrical should be fine.
Problem will be with the lock rack and rod mechanism (mechanical) that reaches down thru the column and activates the ignition switch.
It could also be an ignition switch problem/adjustment, as it is mounted to the column tube.