The best promotion for any church project comes from the pulpit. Make sure the project is officially endorsed by the church and placed on your church calendar. It is a great Vacation Bible School project. It needs to be long enough to raise 84,440 pennies but not so long that your people lose interest. Make copies of it and cut the labels to fit the soda cans, jars, etc.
Award prizes to individuals, classes, etc. who collect the most pennies for the campaign.
Make it fun. Play games, provide refreshments, and apply the labels to your cans, jars, etc. Explain what you're doing and ask the most convenient method, from their perspective, for delivering your pennies. They might require 50-lb. bags. Or they may not have a coin counter and require rolled pennies.