Vatican City - He created more saints than all of his predecessors put together, and now the man dubbed "John Paul the Great" the day after his death may be on the path to sainthood himself.
"He's a strong candidate, there's no doubt," said Patrick Agnew, a Vatican watcher for nearly two decades.
For many in the throngs of pilgrims attending mass in his memory in St Peter's Square on Sunday, the late pope already is a saint.
"The ground he walked on is sanctified," said Julia Isaben, a pilgrim from Guatemala. "Today it is as if covered in flowers," she added.
"He was a great man, really a saint," said Vidiana Crisaculli, who brought her two children to St Peter's Square for Sunday's mass so they could "say goodbye to the pope".
But the Vatican's Congregation for the Causes of the Saints normally takes decades to complete the exhaustive inquiries it deems necessary to confirm miracles attributed to potential saints.
The road to sainthood begins with the attribution of one miracle to the candidate, which if confirmed leads to beatification.
It takes another miracle to achieve sainthood.
So far no one has come forward to attribute a cure to the pontiff, who the Corriere della Sera said on Sunday had died "a public death, like Christ on the cross."
"He used to tell us that in the third millennium one could be a saint, and he showed us," said Davide Annibale, a 21-year-old student from Naples in southern Italy, in St Peter's Square on Sunday.
John Paul II's secretary of state, Cardinal Angelo Sodano, went further, telling Sunday's huge open-air mass that the pope had died with "the serenity of saints".
It was during Sodano's homily that he referred to his former boss as "John Paul the Great".
The burgeoning cult around the barely dead pope is already gathering strength, and the first makeshift shrines to him sprang up around St Peter's Square on Sunday.
Some of the dozens of notes left on lampposts around the square refer to John Paul II in Christ-like terms after the very public suffering he endured in recent years.
"Now that you are resurrected, you remain in our hearts," said one message, written on a paper napkin.
The pope was often referred to as a "living saint", like Mother Teresa, whom he put on the way to sainthood two years before his death with the fastest beatification in Church history, just six years after her death.
Agnew was cautious. "I don't think we can expect much comment about it this week. That would be seen to be distasteful. It would be seen as a campaign by the Congregation for the Causes of the Saints," he told AFP on Sunday.
"It's a slow process. And you have to remember that there was a major row when the pope's elevation of Escriva was seen as being unseemly quick."
The pope controversially made Opus Dei founder Josemaria Escriva de Balaguer, who died in 1975, a saint in 2002. Escriva was just one of 482 saints created by John Paul II, who beatified 1,338 people.
An icon of the sick because of his own illnesses, John Paul II is sure to be invoked often in the prayers of the very ill, and it is likely that sooner rather than later, some will come forward with claims of a miracle, beginning the long process of investigation by the Vatican.
And if some Vatican insiders get their way, the need for proven miracles may be scrapped.
Cardinal Tarcisio Bertone, the Archbishop of Genoa and former secretary of the powerful Congregation for the Doctrine of the Faith, said two years ago that what mattered was not whether people had performed miracles, but whether they had displayed "heroic virtue" -- led an exemplary life.
Few would say that John Paul II had not.