hey fellas and gals

i just pick up a 240sx recently and since i bought it few days ago its been starting up fine.. till today i was at a photoshoot when i started the car to leave it didn't start up so we tried jump starting the car, that didn't work, so we tried push starting the car and it worked. but when i shut off the car and try to start it again the same problem happen it didn't start. but i do here a lil clicking noise when i turn the key other that i dont' hear anythign cranking at all.. does anyone know what the problem is? my friend said it could be the wires to the starter that is lose.. but i wanna know what you guys think! thanks again guys!