[RayInAlaska]

It sounds like the power connection going to the blower motor is intermittent. Most times the reason for things like that is a loose connection along the way. Since you think the ignition switch may be bad, before removing it I would just turn the switch for the blower motor to high, and then listen for the motor to come on/off when wiggling the ignition switch after it has been turned ON to power the blower motor. If the connection through the switch is intermittent, you should hear the motor coming on and going off again.

Summary:

a. Turn the heater switch to high
b. Now turn the ignition switch to ON, and wiggle it to see if it cuts power to the motor

If it cuts power to the motor when you slowly wiggle it, then the switch is the culprit. If it does not cut power to the blower motor, then check for loose connections at all connecting points between the ignition switch and the motor.