key or ignition problem

Have a 92 Seville. Lately, I've had to jiggle the key or gear shift to get the starter to function. Now, nothing but sometimes a buzz, click or just the panel lights go on. Heard that this model has a resistor in the key to prevent thefts. Is there a way I can circumvent this or is the problem the solenoid. I cleaned all the terminals. thanks in advance