I am looking for a better job and have 2 good leads. Should I tell them about each other for leverage?

My current job offers no chance for advancement and miniscule raises as well as a ridiculous amount of beaurocracy. I have leads from two places with good salaries, good benefits, and much chance for moving up, as well as superiors who will actually listen to me. However, I've been waiting to hear from one for a month now, who never returns calls, and the other keeps stalling; it's been more than 4 months for them. Neither employer knows I have other irons in the fire. Should I tell them I have other leads in an attempt to speed the process and let them know there are other interested parties? Or would that backfire and result in my prospects saying "Well, you should go with THEIR offer, then?"