The bookmakers in Europe already have their favorites, but the world won't know who will succeed Pope Benedict XVI until that puff of white smoke is sent up the chimney of the conclave room next month.

The College of Cardinals has no shortage of factors to consider in picking the next pope -- from age to geography -- and no dearth of potential candidates.

Here are some of the princes of the church whose names have emerged from Vatican watchers since Monday's surprise abdication announcement:

Paolo Bona / Reuters

Archbishop of Milan Angelo Scola, attending a funeral in 2012, could be a front-runner to be the next pope.

Cardinal Angelo Scola: He's the archbishop of Milan, a good launching pad for popes, and the former Patriarch of Venice, which has also produced many a papal front-runner. Scola, 71, has close ties to the conservative Communion and Liberation movement, is a champion of immigrants' right and has been active in outreach to the Muslim world. Vatican expert John Allen has written of Scola: "If you like Benedict XVI, you’ll love Scola; even if you don’t, you’ll find it hard not to be charmed."

Cardinal Marc Ouellet: Former archbishop of Quebec, he heads the Congregation of Bishops, a power center. Ouellet, 68, speaks six languages, spent a decade as a missionary in Colombia and has strong ties to Latin and South America. He's considered conservative and made headlines in 2010 when he said abortion was a "moral crime," even in cases of rape. In a 2011 interview, he laughed off the idea of becoming pontiff, saying the workload and responsibility "would be a nightmare."

Ralph Orlowski / Getty Images, file

Cardinal Marc Ouellet celebrating Mass in 2012.

Cardinal Leonardo Sandri: Born in Argentina to Italian parents, Sandri was No. 2 in the Vatican Secretary of State's office under Pope John Paul II and now serves as prefect of the Congregation for the Oriental Churches. A longtime Vatican diplomat, Sandri, 69, is well-respected but seen by some as more of a top-notch administrator than a theological leader. 

Stefano Relandini / Reuters

Cardinal Gianfranco Ravasi looks on at Palm Sunday mass in Saint Peter's Square at the Vatican.

Cardinal Gianfranco Ravasi: The Italian-born president of the Pontifical Council for Culture, Ravasi, 70, is hugely popular through his Scripture lessons on TV and radio. On a crusade to keep the church relevant, he blogs, quotes Amy Winehouse on Twitter, and criticizes priests for boring sermons. An archaeologist by training, he's a brainy biblical scholar who is seen as a theological moderate.

Cardinal Angelo Bagnasco: The archbishop of Genoa is well-connected, having served twice as the president of the Italian bishop's conference. A baker's son who says he knew he wanted to be a priest in elementary school, Bagnasco, 70, is considered a conservative force in the church. He was the target of death threats in 2007 after comments opposing same-sex unions and in 2011 he launched a thinly veiled attack on scandal-ridden Italian Prime Minister Silvio Berlusconi and other politicians, referring to them as "sad and hollow." 

Max Rossi / Reuters, file

Cardinal Peter Turkson of Ghana arriving for a Mass at St. Peter's Basilica at the Vatican in 2005.

 Cardinal Peter Turkson: The first Ghanaian cardinal, he's president of the Pontifical Council for Justice and Peace and the Vatican’s point man on Catholicism in Africa. An energetic 64 years old, Turkson is considered to be more moderate than some other contenders but hardly a radical. Asked about the spread of AIDS in Africa, he said abstinence was a better solution than condoms. A couple of years ago, he said the first black pope would have a "rough time" and he wasn't bucking for the job.

Cardinal Odilo Scherer: Born in Brazil to parents of German extraction, Scherer's big advantage is geography; he hails from the region that is home to half the world's Catholics. Considered a moderate, the 63-year-old serves as the archbishop of Sao Paulo and has spots in two key Vatican groups, the Congregation for the Clergy and the Pontifical Council for the Promotion of the New Evangelization. 

Cardinal Timothy Dolan: The head of the archdiocese of New York is one of the Vatican's most popular figures -- charismatic, camera-ready and conservative. As head of the United States Conference of Catholic Bishops, he hasn't shied from away from political fights, taking on the Obama administration over contraception. But Dolan, 63, has only been a cardinal for a year.

Mark Lennihan / AP

New York Cardinal Timothy Dolan speaks to the press in his residence after the announcement that Pope Benedict XVI will abdicate.

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