VATICAN CITY – Bringing their suitcases and personal views on the future of the church, the cardinals who will select the next pope settled in their rooms yesterday into the Vatican hotel that will be their home until the world’s 1.1 billion Roman Catholics have a new leader.

The conclave starts today after the 115 red-robed cardinals join a formal procession into the Sistine Chapel, where efforts to maintain the secrecy of deliberations have included installing jamming devices to foil sophisticated eavesdropping equipment.

But the cardinals’ arrival at the $20 million Domus Sanctae Marthae took them into the imposed isolation of the papal election, which has not lasted longer than five days in the past century but remains an open-ended process. The last conclave in 1978 took eight ballots over three days to choose Pope John Paul II.

“The new pope has already been chosen by the Lord. We just have to pray to understand who he is,” Florence Cardinal Ennio Antonelli told the congregation at St. Andrea delle Fratte, his titular church a short stroll from Rome’s famous Spanish Steps.

The cardinals have much to ponder following the third-longest papacy in history.

This conclave feels the full weight of the church’s modern challenges, including the influence of Islam, competition from evangelical Christians, the fallout from priest sex scandals, the roles of women, and the need to reconcile Vatican teachings that ban condom use with worries about AIDS. They also must seek a global pastor with enough charisma to flourish in an image-driven age.

For the first time, credible papal contenders come from at least three distinct regions: Europe, Africa, and Latin America.

One by one, in cars driven by aides through a steady rain, the cardinals arrived at the gates of Vatican City. They were saluted by a single Swiss Guard, wearing a dark foul-weather cloak over his traditional uniform of purple, gold, and red. The cars passed over gray cobblestones to the hotel – which John Paul II ordered built to end the spartan quarters arranged for past conclaves.

The rules of the conclave are strict: no phones, television, publications, or outside contact. All staff – including cooks, maids, elevator operators, and drivers who will shuttle them the few hundred yards from the hotel to the Sistine Chapel – have taken vows of silence.

For the first time ever, cardinals will be allowed to move about Vatican City freely once the voting starts, though they are forbidden to talk to anyone who hasn’t been sworn to secrecy. The penalty is severe – excommunication.

At the North American College seminary, some of the 11 American cardinals joining the conclave posed for a group photograph before making the five-minute trip to the Vatican. Cardinal Roger Mahony of Los Angeles carried a set of red robes in a clear garment bag and a small overnight bag hung from one shoulder. They made no comments to reporters.

The Turin daily newspaper La Stampa reported that many cardinals, preparing for a stressful stretch ahead, had packed compact-disc players and headphones along with prayer books and their red hats. Other prelates, it reported, brought along favorite snacks.

The public will get one more chance to view the cardinals before they begin their deliberations. This morning, a special Mass at St. Peter’s Basilica is scheduled in the memory of John Paul II, who died April 2 at the age of 84 and is buried with many other popes in the grottoes reached by stairs near the altar.

Later in the day, the cardinals will gather in the Apostolic Palace for a procession to the Sistine Chapel while chanting a hymn seeking inspiration from the Holy Spirit.

The cardinals will then hear a prayer in Latin by the dean of the College of Cardinals, German Cardinal Joseph Ratzinger, to be guided “in our hearts in love and in patience.” Cardinal Ratzinger, 78, is considered a possible papal candidate.

Once inside the chapel, the prelates can decide to hold a single ballot. If not, they will begin voting tomorrow morning with four ballots a day. At least 77 votes – or two-thirds of those attending – are needed to elect a pontiff during initial balloting. Under rules updated in 1996 by the late pontiff, it could shrink to a simple majority at some point in the second week.

Another new element comes with this conclave: Bells will ring after a new pope is chosen in an effort to avoid confusion over the color of smoke wafting from the chapel’s chimney. The smoke is black if balloting fails to produce a pontiff and white if a choice is made.

The next pope’s name will be announced from the central balcony of the basilica a short time later.

Italians – who hold the largest national bloc in the conclave with 20 cardinals – apparently have struggled to reach a consensus on whether to back one of their own for the papacy, a Vatican expert for the Rome daily newspaper La Repubblica, Marco Politi, wrote.

The Polish-born John Paul II was the first non-Italian pope in 455 years. Several Italians have been mentioned as papal prospects, including Milanese Cardinal Dionigi Tettamanzi.

Cardinals who are less than 80 years old and allowed to participate in the conclave agreed not to give interviews during their daily meetings to prepare for the gathering. The source for La Repubblica’s assessment was not mentioned.

Italian Cardinal Salvatore Pappalardo, who at 86 is too old to vote, indicated in remarks on Italian state radio yesterday that he believed his younger peers would be looking for a candidate who would be in tune with global problems – particularly issues of justice, peace, and even the environment.

“Providence sends a pope [to meet the needs] of every era,” he said.