ROME, April 17 -- Sequestered behind Vatican City's medieval walls, 115 Roman Catholic cardinals from 52 countries begin Monday to choose a successor to Pope John Paul II in a secret conclave that will follow elaborate rules both written and unwritten, ancient and new, spiritual and political.
The cardinals arrived by foot and by car Sunday at the Domus Sanctae Marthae, the Vatican guesthouse where they will sleep and eat during the conclave. All were dressed in their traditional red-trimmed black cassocks, their waists wrapped in scarlet sashes and their heads bobbing beneath scarlet skullcaps. Already forbidden to speak to reporters, they will take a vow of complete secrecy when they enter the Sistine Chapel on Monday. There, under Michelangelo's depiction of a stern Christ delivering the Last Judgment, they will mark their ballots at long tables covered with golden cloths.
Cardinal Roger M. Mahony of Los Angeles hands his robe to his driver as he leaves the North American College in Rome for the Vatican.
(Gregorio Borgia -- AP)
Video: Cardinals gathered at the Vatican celebrate Mass prior to beginning a conclave to select a new pope in the Sistine Chapel.
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To become pope, a candidate must receive a two-thirds majority, or 77 votes, in the early rounds of balloting. Most conclaves in the past century have lasted only three or four days. But if the cardinals remain deadlocked for more than 12 days, they can change the rules and elect the pontiff by a simple majority -- an innovation introduced by John Paul that has never been tried before. The ballots are burned in an old stove, and when someone wins, a chemical will be added to turn the smoke white.
On Sunday, some of the cardinals celebrated Mass at churches they are nominally assigned to in Rome. None was tipping his hand. During a sermon at the church of San Giovanni della Pigna, Cardinal Francis Arinze of Nigeria told the congregation that the next pope "should be a preacher" and "a shepherd who sacrifices himself for the people of God."
At the church of San Andrea delle Fratte, Cardinal Ennio Antonelli, the archbishop of Florence, said: "The new pope has already been chosen by the Lord. We just have to pray to understand who he is."
Before going into Vatican City, Cardinal Oscar Andres Rodriguez Maradiaga of Honduras told reporters: "People think we are going to vote like in an election, but this is something completely different. We are going to listen to the Lord and listen to the Holy Spirit."
Arinze, Antonelli and Rodriguez have all been touted as papal possibilities.
Cardinals frequently ascribe the choice of a pope to the workings of the Holy Spirit. But the history of conclaves in the last half of the 20th century also shows marked similarities with the formation of governments by fractured parliaments. Passions run high, personalities count, quick thinking can make or break a candidacy.
Once inside the Sistine Chapel, the cardinals traditionally vote in silence, raising their voices only for collective prayers, procedural announcements and vote counting. Custom prohibits speeches for or against a candidate, but that does not mean it can't happen. "Somebody can get up and say something if he feels inspired to do so. What are they going to do, stick his head in the oven?" said George Weigel, a papal biographer. "It's not customary. I rather doubt it's going to happen, but there's really nothing to prevent it."
The most famous recent case of a Sistine Chapel outburst came in 1963, when the contest came down to Cardinal Giovanni Battista Montini, archbishop of Milan, and Cardinal Giuseppe Siri of Genoa. Siri aroused opposition because many feared he would place obstacles in the way of the Second Vatican Council, which had been convened in 1962 by Pope John XXIII to modernize and democratize the Catholic Church.
A friend of the late pope, Cardinal Gustavo Testa, grew alarmed at the deadlock. He favored Montini as John XXIII's successor. According to varying accounts, he said either in a short speech or a loud stage whisper that the cardinals should stop their "squalid maneuverings" and consider the good of the church. Siri objected to the breach of etiquette and tried to shout Testa down. Montini rose to withdraw his candidacy. But Cardinal Giovanni Urbani of Venice grabbed Montini by the arm and hissed at him, "Your eminence, shut up!" Montini was elected and became Pope Paul VI.
Such dramatic exceptions aside, the discussions about who would make the best pope are likely to take place outside the Sistine Chapel. The cardinals will have plenty of opportunity for informal contact, both one-on-one and in small groups.
"You can assume there will be caucusing, knocking on doors at night, conversations around the dinner table, conversations on the terrace," said John-Peter Pham, a former Vatican diplomat and author of "Heirs of the Fisherman," a 2004 book on papal successions. "Electors have been known to hold meetings in whatever quarters they could find: the smokers' group, the strollers' group, around the brandy bottle."
In the Middle Ages, would-be popes often bought votes with promises to provide lucrative positions to electors' relatives. Making material promises in return for support, known as simony, is now prohibited under penalty of excommunication. Moreover, custom dictates that candidates should not personally ask for votes or make any promises about what they would do as pope.
"You can't solicit votes, but a friend or ally can. So you have to have someone, or some group, who will lay out your platform and talk about your qualifications," said Frederic Baumgartner, a history professor at Virginia Tech in Blacksburg and author of a 2003 book, "Behind Locked Doors: A History of Papal Elections."
The result is that Vatican watchers pay as much attention to possible kingmakers as they do to possible candidates. In this conclave, either role could be played by Cardinal Joseph Ratzinger, a German-born champion of orthodoxy and continuity with the papacy of John Paul. In recent months, Ratzinger has made harsh attacks on secular Western culture. On Saturday, Walter Kasper, another German cardinal and head of the Vatican's department in charge of trying to unify Christian groups, gave what appeared to be an anti-Ratzinger sermon. "Let's not search for someone who is too scared of doubt and secularism in the modern world," he said.
In theory, the conclave could elect any baptized male, though he would have to be ordained as a priest and bishop before assuming the papacy. In practice, the contest is limited to the 115 cardinals, all under 80 years old, who have been meeting in closed sessions for the past two weeks to discuss the state of the church and to size up one another. In three of the last eight papal elections, the front-runner was apparent in advance and emerged as pope. But Vatican watchers consider this election hard to read, with more than a dozen cardinals frequently mentioned as contenders.
The conclave will follow centuries-old rules that were revised by John Paul in 1996. On Monday morning, the cardinals will attend a Mass at St. Peter's Basilica. In the afternoon, they will walk in a procession from the Vatican's Apostolic Palace to the Sistine Chapel, take the oath of secrecy and listen to a sermon on their sacred duty. After a cry of "Extra omnes!" -- Latin for "Everyone out!" -- only the voting cardinals will remain in the chapel.
They may hold an initial round of balloting Monday afternoon, or wait until Tuesday morning to begin voting. In either case, starting Tuesday there are to be four ballots per day, two in the morning and two in the afternoon. This nearly continuous voting reduces the opportunities for organized politicking -- for the cardinals to adjourn, discuss the situation with colleagues and shift their votes in blocs.
Instead, judging from past conclaves, they will closely watch the momentum of the vote counts and make individual, on-the-spot decisions as to whether to support, or oppose, any candidate whose vote total begins to surge toward the threshold of 77.
"In a conclave, if you are not moving forward, you are moving backwards," said Alberto Melloni, a historian of Catholicism.
If no one has been elected after three days of balloting, the cardinals can take a day-long break for prayer, discussion and a "spiritual exhortation" by a senior cardinal. Balloting would then resume, with a similar break and an address by another senior cardinal after every seven rounds of voting.
After the fourth break -- which would come on about the 12th day -- the rules set by John Paul allow the cardinals to vote, by simple majority, to lower the threshold for election from two-thirds to 50 percent plus one. The pope could then be elected by 58 of the 115 votes, a major departure from tradition.
Some experts contend this change provides an incentive against compromise. Theoretically, if a candidate musters a bare majority but not two-thirds in early voting, his backers could simply hold tight through about 30 ballots and then prevail.