April 18 (Bloomberg) -- Pope John Paul II, the third-longest serving pope in history, laid the groundwork for a successor who shares his views on birth control and celibacy to emerge from election of his successor that begins today.

During his 26-year tenure, John Paul II appointed all but two of the 115 voting cardinals and reduced the influence of Italians by favoring men from the developing world. He also modified the rules of the so-called conclave to make it easier to avoid a voting deadlock.

``This conclave is the most diverse geographically, but you might say it is the most homogenous theologically,'' Frank J. Coppa, a papal historian at St. John's University in New York, said in a telephone interview.

The cardinals who gathered at St. Peter's hail from 52 countries, and about half of them are from outside Europe. Italians account for 17 percent, down from 23 percent when John Paul II was chosen in 1978. The Polish-born pontiff was the first non-Italian pope in 455 years, and his tenure was surpassed only by Pius IX in the 19th century and St. Peter.

In his homily to the College of Cardinals at a morning Mass in St. Peter's to begin the conclave, German Cardinal Joseph Ratzinger, 78, said the cardinals shouldn't stray from John Paul II's orthodoxy. Ratzinger denounced the risk of relativism, the belief that there is no truth, and urged the so-called princes of the church not to give in to calls for change.

`Dictatorship of Relativsim'

``We are moving toward a dictatorship of relativism, which does not recognize anything as certain and which has its highest goals ones own ego and desires,'' he said.

Ratzinger is considered among the leading candidates, according to Paddy Power, Ireland's biggest online bookmaker. Ratzinger is deal of the college of cardinals and led the funeral Mass for the pope. U.K. bookmaker William Hill Plc last week had Nigerian Francis Arinze as favorite, before support also shifted to Ratzinger.

Brazilian Cardinal Claudio Hummes has been mentioned as a candidate by the U.K.'s Guardian newspaper. Other leading contenders detailed by bookmakers and the press include Italian cardinals Dionigi Tettamanzi and Angelo Sodano, and prelates from France, Argentina and Honduras.

That his successor may have dealt with AIDS victims in Africa or struggled to convince young men in Latin America to become priests and accept celibacy instead of joining the spreading evangelical movement doesn't mean a pope from those parts of the world would do anything to ease the Church's opposition to birth control or celibacy, according to Cardinal Francis George.

Doctrine Won't Change

``Your solution is to exterminate the poor?'' George, who will vote in the conclave, said at an April 5 press conference in Rome when asked about condom use to prevent AIDS. ``The doctrine of the church isn't going to change, and so you work with it as best as you can.''

The election of the new spiritual leader to the world's more than 1 billion Roman Catholics is purely democratic. All cardinals cast votes for whomever they see fit and the results are read out loud, allowing the cardinals immediately to gauge shifts in support before the next vote. The first ballot may be held later today.

If no Cardinal secures a two-thirds majority, the papers will be burned with a chemical to produce black smoke. This will tell the world the voting continues.

Pope's Presence

One of the first things the cardinals see when they enter their quarters, the 129-room Santa Marta residence, is a bronze bust of the late pope, and his portrait hangs outside the chapel where they will go for divine inspiration.

There are as many as four votes a day, behind the closed doors of the Sistine Chapel, beneath Michelangelo's famed image of God breathing life into Adam. Support can quickly shift to a dark-horse candidate if two cardinals split the vote and can't get the two-thirds majority needed.

In 1978, Karol Wojtyla was a little-known cardinal from Krakow when he was elected on the second full day of the conclave, after the men were divided on two Italians who were considered favorites.

It has been more than 150 years since a conclave lasted more than five days. John Paul II changed the rules in 1996 so that if a deadlock continues for about 12 days and as many as 30 votes, the cardinals can elect a pope by simple majority.

``As soon as someone gets a majority, the other cardinals will know that all the supporters have to do is sit tight until they can get their man in,'' said Father Thomas Reese, editor of America magazine and author of the book ``Inside the Vatican.'' ``They will say `vote him in and let's go home.'''

Coercion

The name conclave comes from the Latin for ``with key,'' referring to the fact the cardinals were locked in to coerce them to make a speedy decision.

In 1271, the cardinals weren't only locked into the conclave, the roof was taken off the building and they were fed nothing except bread and water in a bid to quicken the process. That's a far cry from the Santa Marta, where for the first time the electors will each have en suite bathrooms, a welcome relief for a group of men whose average age is more than 70.

There is a saying in Rome that he who enters the conclave a pope, comes out a cardinal. Still, the Italian press has been full of speculation about shifting alliances among the cardinals, and odds have been fluctuating dramatically on Internet sites taking wagers on the outcome.

`Papabiles'

Ratzinger's star may be rising after leading the funeral Mass viewed by hundreds of millions of people around the globe and delivering the homily for his friend. Ratzinger, one of only two voting cardinals not appointed by the former pontiff, served as head of the Congregation on the Doctrine of the Faith, which is charged with enforcing church doctrine. He would likely have a relatively short papacy, something that might be favored by the cardinals after the more than quarter-century reign of John Paul II.

Dionigi Tettamanzi is considered among the leading Italian ``papabiles'' as the possible future popes are referred to in Italian. The 71-year-old archbishop of Milan has praised the Opus Dei movement while defending anti-globalization protesters, showing he shares John Paul's progressive views on some social issues though toes the line on Church orthodoxy.

Nigeria's Cardinal Francis Arinze, 72, and Oscar Rodriguez Maradiaga of Honduras, are considered among the strongest of the non-European candidates. Arinze converted to Catholicism as a child and became Africa's youngest bishop at the age of 32.

Rodriguez Maradiaga is a mathematician and musician who speaks eight languages and campaigned for debt relief alongside U2 lead singer Bono.

``The cardinals will look first at Italian candidates,'' Reese said. ``It's very natural to do that. Rome is an Italian city and the pope has to be bishop of the people of Rome. But there is no single Italian that all the Italians are united behind.''

To contact the reporter on this story: Andrew Davis in Rome at abdavis@bloomberg.net.

Last Updated: April 18, 2005 07:04 EDT