i had this problem before.
first thing i did was to wiggle around the steering and turn the ignition to see if it would start. This method DID NOT work.
the second i got a wiring diagram and went through all the earthing points on my car (r32gts) and basically replaced them or screw them properly. This FIXED the problem, but it might be different for you.
so if it is an electrical problem just check your earthing first and go from there.