1999 Mercury Cougar I need some help! She doesnt want to fi

I have a rapidly progressing problem with this cougar. When I turn her over it turns over but doesnt want to fire. pumping the gas seems to help and it will start. after its started it may die two to 5 times before it will stay on. I have to keep the RPMs up to not give it the chance to die and it will usually stay on. Strong smell of gas in the car after starting it from pumping the pedal. I am not sure if this is electrical or something else. It usually wont die when driving. It has on occassion died when at a stop light and the RPMs drop. but most the time it wont. Last week it died twice while i was mid drive?! help me out, i would like ot fix this problem myself but not sure where to start. I have already replaced the spark plugs, and wiring.