To check if its a switch problem or a resistor , run a wire directly from the positive side of the battery to the + side of the coil. Start the car as you normally would, (just be aware that you won't be able to shut it off without yanking that new wire).
If the car runs O.K., that narrows the problem down to bad switch or resistor.
Disconnect the resistor and run a jumper wire in its place (it won't hurt to do this for 15 minutes or so)----if the problem still occurs, then the switch is bad.