VATICAN CITY The cardinals who enter the papal conclave on Tuesday will troop into the Sistine Chapel in single file, but beneath the orderly display, they are split into competing lineups and power blocs that will determine which man among them emerges as pope.
The main divide pits the cardinals who work in the Vatican, the "Romans," against the "reformers," the cardinals who want the next pope to tackle what they see as the Vatican's corruption, inefficiency and reluctance to share power and information with bishops from around the world.
But the factions in this conclave do not break along geographical lines, and in fact, they have produced surprisingly counterintuitive alliances: The Romans' top preference appears to be a Brazilian, and the reformers are said to want an Italian.
This conclave is far more unpredictable and suspenseful than the last because the church landscape has shifted in the last eight years. The next pontiff must unite an increasingly globalized church paralyzed by scandal and mismanagement under the spotlight in a fast-moving media age. And among the cardinals, there is no obvious single successor to Pope Benedict XVI, who rattled the church by resigning last month at age 85.
With all of the uproar over Vatican scandals, the Romans are aware that they may fail if they back one of their own, and so they are said to be coalescing behind the Brazilian, Cardinal Odilo Pedro Scherer, the archbishop of Sao Paulo.
Scherer is of German heritage, but his selection would give the Roman Catholic Church its first pope from Latin America. The region is home to about 40 percent of the world's Catholics, and the church is staving off challenges there both from surging evangelical churches and a drift toward secularism.
The reformers, led by the Americans and some influential Europeans, are reportedly uniting around the Italian, Cardinal Angelo Scola, the archbishop of Milan, a popular pastor and an erudite moral theologian. As an Italian, he is familiar with the culture that dominates the Vatican bureaucracy, but he is not a part of it or beholden to it.
Many cardinals, however, say they are eager for a pope from outside Italy and better yet, from outside Europe, an appointment they hope would energize the world's 1.2 billion Catholics.
Whoever he is, he will have to convince his fellow prelates that his gifts as an evangelist and an administrator can move the church past the scandals involving child sexual abuse, the Vatican bank, the recent resignation of a cardinal who admitted he had used his own priests for sexual favors, and the so-called VatiLeaks episode in which the pope's personal papers were stolen and published, revealing bitter infighting in the church's central administration, known as the Curia.
The last conclave eight years ago presented a far simpler scenario. There was one dominant candidate to beat going in, and that was Cardinal Joseph Ratzinger, the longtime head of the Vatican's office on doctrine and the close collaborator of the previous pope, John Paul II. He was elected on the conclave's second day after just four ballots and took the name Pope Benedict XVI.
The alignments then were animated by theological differences, with the dwindling pool of liberal cardinals backing alternatives to Ratzinger whom others might find acceptable. But this time, there are not enough theological liberals among the cardinals to create a viable bloc.
For the first time, an American could be poised to overcome the conclave's traditional aversion to a pope from a superpower, though not all analysts agree on this.
The most likely contenders are: Cardinal Timothy Dolan, the archbishop of New York, known for his exuberant presence and evangelizing skills; and Cardinal Sean Patrick O'Malley of Boston, a Capuchin Franciscan friar, who has a reputation for having calmed the waters in three successive dioceses (Fall River, Mass.; Palm Beach, Fla.; and Boston) ripped up by child sexual abuse scandals. Both have spoken out in favor of change.
Gian Guido Vecchi, a journalist who covers the Vatican, said in the Italian newspaper Corriere della Sera last week, "Even if this won't be the time for the first American pope, it's difficult to imagine that the pope can be elected without, or even against, them."
Some cardinals are considered long shots as candidates, but they could still play kingmakers whose endorsements carry great weight.
One kingmaker for the reformers is Cardinal Christoph Schoenborn, the archbishop of Vienna, a savvy diplomat descended from nobility who studied with the emeritus pope Benedict. Schoenborn supports Scola, the archbishop of Milan, according to Carlo Marroni, a Vatican expert for the Italian business newspaper Il Sole 24 Ore.
If neither the Romans nor the reformers have the votes to elect their front-runners, there are compromise candidates who might pull enough votes from both camps to win, the analysts say.
One name mentioned even before Benedict's resignation is that of a Canadian, Cardinal Marc Ouellet. He is a doctrinal conservative who taught philosophy in Colombia and may have support from some Latin American cardinals.
But Ouellet has spent many years working in the Vatican and has led the department for bishops since 2010. He could be seen as a crossover candidate acceptable to both Romans and reformers.