Help needed: engine cranks but does not start

Just wondering if anyone out there ever experienced the engine turning but not starting as though the car had no fuel. If anyone has had the same prob and gotten it fixed what did it turn out to be?It started out a few weeks ago as though the car was going to cut out on me right after start-up and has since gotten worse to the point where I have to stay on it for a good 4-5 sec a few times in a row before I can get it to start. Would it be a bad fuel pump? Otherwise do relays go bad? I've also had wiper problems recently (someone suggested it might be the relay) and was wondering if something could have caused the relays to malfunction.