I need help please!!

I went out to start my jeep this morning and when it started it had a miss at idle. If i rev the motor a bit a went away. I also had plenty of power when i actually drove. It seems that the more it warms up the better it runs but always seems to have a slight miss at idle . Any ideas?
Thanx Digger

My guess is....plug wire loose or worn/broken. You should be able to narrow it down to what cyl is missing by pulling plug wires off one at a time and running it to see which one does not make a difference...just a guess..