Fans of traditional doctrine bet on Cardinal Dario Castrillon Hoyos, a Colombian who has stood up to his country's ruthless drug lords. Some Vatican insiders are partial to Cardinal Giovanni Battista Re, Pope John Paul II's chief of staff. But among those speculating about who the next pope will be, the big money literally is on Joseph Ratzinger, who delivered a stirring homily at the late pope's funeral.
A number of Internet gambling sites are taking bets on who will come out of the upcoming cardinals' conclave as the new leader of the Roman Catholic Church. Some bricks-and-mortar bookmakers in Britain, Ireland and Europe are also in on the game, though Las Vegas and Atlantic City have shied away from the Vatican action. The official papal selection process begins in Vatican City on Monday and is expected to choose a successor to John Paul within a few days.
As of Thursday, most gambling sites gave Ratzinger, a German who was one of John Paul's closest advisers, the best odds, with a host of second-tier candidates not far behind. Among them are two elderly cardinals retired archbishop of Paris Jean-Marie Lustiger and Carlo Maria Martini of Italy.
There are also several non-European candidates, although bettors appear to be less confident now than a week ago that the next pope will come from the developing world. There's even a non-cardinal among the very longshots on one site, Boston Archbishop Sean O'Malley.
Can these Internet gambling dens possibly predict what will happen in the Vatican's inner sanctum next week?
Papal prognostication is notoriously difficult. The deliberations occur in secret; openly campaigning for the papacy is taboo. And the cardinals who will choose the next pope voted unanimously not to talk publicly at all until the decision is made.
"It is a futile effort, although it can be rather fun to speculate and even bet," said Greg Tobin, author of a book on the papal selection process.
The favoured candidate going into the conclave is so rarely the man who ultimately steps out onto the balcony of St. Peter's Basilica wearing the papal vestments that Vatican watchers have a saying: "He who enters the conclave a pope, emerges a cardinal."
Even so, economists have been surprised at how well the aggregated guesses of bettors align with the real likelihoods of different outcomes in all sorts of events. In economic terms, bettors are essentially traders in an efficient market, where prices are very close to the actual values of whatever is being bought and sold.
"If the ... market says (Nigerian Cardinal Francis) Arinze has a 25 per cent chance, I'd have to be a serious papal expert before I'd even dream of thinking I knew better," Stanford University economist Eric Zitzewitz said in an e-mail message.
Betting markets have outdone pundits, polls and the press in predicting other elections.
During the past four U.S. presidential campaigns, economists at the University of Iowa have operated an Internet-based futures market where anybody who wants to can bet on one of the two major-party candidates.
In the extremely tight 2004 election, for example, virtually every authoritative source considered the race too close to call right up to election night. But the Iowa market gave George W. Bush a clear edge from the end of the Republican convention in early September.
It isn't that the candidate supported by the majority of bettors always wins. If that were the case the outcome could be determined by a simple head count and there wouldn't be anything to bet on. The idea is that on average, the proportion of bettors who put money on a given candidate reflects that person's actual chances of winning at the time the bets are placed.
"If the prediction market says the probability of an event is 30 per cent , the event happens almost exactly 30 per cent of the time," Zitzewitz said.
But that assumes a large number of bettors have accurate information about whatever it is they are wagering on, he cautioned. And when you're talking about selecting a pope, that may not hold.
"Even the cardinals themselves are working through this to determine exactly what criteria, what strengths they'll be looking for in the candidates," Tobin said. "That's where the futility comes in."
Besides obvious candidates, there are many cardinals in the elite group the Italians refer to as the "papabili." The process is so complex and opaque as to be virtually unpredictable. And as Tobin noted, "you've got the Holy Spirit as the pit boss in this casino."
The odds may be long. But good Catholics can feel free to speculate about whose name will be announced when the white smoke finally flies and even put a little money on it.
Yes, gambling is acceptable as long as it is pursued for fun rather than profit and does not impinge upon the bettor's ability to provide for his needs or those of his dependents. That's according to the Roman Catholic catechism.