When the cardinals enter the Sistine Chapel on Wednesday at the start of conclave, the process of electing a new pope, they will be sealed off from the world.

The United States is the home country for 10 of the 133 cardinals eligible to vote for the next pope. That's more than any nation except Italy, home to 17 of the electors who will gather Wednesday for the Vatican conclave to choose the successor to Pope Francis.

As the conclave to elect the next pope begins Wednesday at the Vatican, four candidates have emerged as clear favorites—Cardinals Pietro Parolin, Luis Antonio Tagle, Matteo Zuppi and Pierbattista Pizzaballa.

Cardinal Luis Tagle, the archbishop of Manila in the Philippines, was appointed by Pope Francis to an office in the Vatican that focuses on evangelization. ABC News' Britt Clennett reports.

The process of electing the next pope begins Wednesday in Vatican City with the voting members of the College of Cardinals sequestered inside the Sistine Chapel and cut off from the outside world until they make their choice.