"Pope Francis has told me that he is coming," Chaput said Thursday (July 25) before delivering a homily at a Mass in Fargo, N.D.
Chaput, a member of the Prairie Band Potawatomi tribe, was in Fargo for a conference on Native Americans and invited his fellow Native Americans to the Eighth World Meeting of Families, set to take place in Philadelphia from Sept. 22-27, 2015.
"The pope will be with us the Friday, Saturday and Sunday of that week," Chaput said, according to Catholic News Service. That would be Sept. 25-27.
Only the Vatican can officially confirm a papal visit, and such an announcement is not expected until six months or so before the visit.
A follow-up statement by the Philadelphia archdiocese on Friday reiterated that fact and said that while Chaput's comments "do not serve as official confirmation, they do serve to bolster our sincere hope that Philadelphia will welcome Pope Francis next September."
The statement said that Chaput's "personal conversations with the Holy Father are the foundation for that confidence."
The Vatican also sought to rein in speculation on Friday, issuing a cautious statement saying that Philadelphia is one of several invitations that Francis "is carefully considering."
"The Holy Father has indicated his willingness to participate" in the Philadelphia event, said the Rev. Federico Lombardi, a Vatican spokesman.
But, he added, "at the present moment, there are no concrete plans or programs for any visits to the United States or Mexico. Keep in mind that we are still one year away from the Philadelphia meeting."
A papal visit to Philadelphia has been a likelihood since June 2012, when then-Pope Benedict XVI announced that the city would host the global Catholic conference on family life, and that he intended to be there.
When Benedict resigned in February of 2013 and Francis was elected two weeks later, it was assumed that the new pope would also make the trip; a native Argentine, Francis has never been to the U.S. in any capacity.
Vatican officials have been visiting Philadelphia in recent months to start organizing the daunting logistics entailed in a papal visit and the massive crowds that the popular Francis will surely draw.
Also, in 2012, the Knights of Columbus, a leading Catholic charitable organization, donated $1 million to the archdiocese as a down payment on the enormous costs of the visit.
The money is key: Philadelphia has been hit hard by legal fees and settlements from the clergy sex abuse scandal, and declines in churchgoing and contributions have forced Chaput to make painful cutbacks to programs and to close parishes. It was unrealistic to expect the cash-strapped archdiocese to foot the bill for the trip.
The real question now may be where else the pontiff will visit: New York? Washington? Maybe even the border with Mexico to make a statement on immigration?
All three venues are possible, even likely.
New York has been a priority for every pope who has visited the U.S. since pontiffs began traveling internationally in the 1960s, and the United Nations General Assembly will be in session in late September 2015. Church observers say it's hard to believe Francis will not address the world body to press his concerns about world peace, human rights, and economic inequality.
A stopover in Washington is also a possibility.
Last March, on the first anniversary of Francis' election, House leaders invited Francis to become the first pope to address a joint session of Congress. Other popes have visited the White House. Benedict was the last to do so, meeting President George W. Bush there in 2008.
The real wild card is the possibility that Francis would visit the U.S. border with Mexico, as Mexican leaders and some church officials have said he might. That would make a powerful statement about immigration, a contentious issue in American politics.
Francis has made the treatment of migrants and refugees a core theme of his pontificate: He traveled to the Italian island of Lampedusa in his first official papal trip to celebrate Mass in memory of the untold numbers of Africans who have drowned in desperate efforts to flee poverty and danger.
That act inspired a Mass on behalf of immigrants that leading U.S. bishops celebrated in Arizona in April at the 30-foot security wall that the U.S. has built along the U.S.-Mexico border.