The Pennsylvania delegation will go to Rome in two weeks to formally invite the Holy Father to attend the World Meeting of Families, which comes to Philadelphia in September 2015.
Although the event was planned under Benedict XVI, Chaput said he is confident Francis will attend the meeting, which would be the new pope's first trip to the United States and could draw more than a million people to Philly.
Chaput said he hopes Francis will give an outdoor Mass if he comes, as Pope John Paul II did on the Benjamin Franklin Parkway in 1979.
A papal visit would have an enormous economic impact for Philadelphia, Nutter said.
"In other cities, it's been in the millions," he said. "You put that many people in a place for four or five days, they're going to spend a lot of money."
Meeting Francis, the first Jesuit pope, will be a special moment for Nutter, who learned from the scholarly order of priests at St. Joseph's Prep, he said.
"At the heart and soul of it, it is about being a man for others," Nutter said of the Jesuits' message. "It will make the event that much more special."
President Obama will be in Italy the day after the Pennsylvania delegation leaves Rome. On his trip, Obama plans to meet Francis.
On Twitter: @SeanWalshDN