Apparently my car only stays on if I hold the key in the on position. I usually rev it pretty good a couple times and it stays on. not tonight I thought to myself "I'm done no more starts" I try again. Turn the key give it gas. it starts. I'm holding the key down reving it. So I can hear the starter pretty good. With my left hand reach across put it in 1st take off and let go of the key. it studderd but stayed on and I got home. I wanted to share this experience. hopefully someone can use this trick to get home or help someone else. I'm going to fix it tomorrow. I hope.

 

If you have to turn the key or keep weight on the key to keep the car running, it is most likely the ignition switch is worn.
~$30 from Rockauto.

 

If the lock cylinder is also loose you should replace it while you're at it.