For the first time, the majority of cardinals to choose a pope are not from Europe, as Catholic demographics shift. But Europe remains the largest source of cardinals.

Of course, there's a betting market for the next pope. And they favor two cardinals over the rest of the field.

All of the 133 cardinals expected to take part in the secret conclave to elect a new pope have arrived in Rome, the Vatican said on Monday, with the race to succeed Pope Francis seen as wide open.