As others have said, your problem is likely the solenoid. There is a copper disc inside that rotates when you turn the ignition. It causes the solenoid to engage. Over time, the copper burns and therefore doesn't engage. Click it enough times, and it may ultimately find a clean spot and start the motor. There was a time when you could open the solenoid and just flip that copper disc over. Most solenoids now, however, are not serviceable.
2005 X9 350MCX