All cardinals under 80 years old are eligible to vote for the successor to Pope Emeritus Benedict XVI, who retired on February 28. That leaves 115 cardinals who will vote at the Sistine Chapel up to four times a day until two-thirds (77 cardinals) agree on who the new leader of the Roman Catholic Church should be.
The conclave to elect Benedict in 2005 lasted only two days, which signaled that cardinals generally agreed on the election, but conclaves can potentially last much longer if there's no consensus.
"The eighth General Congregation of the College of Cardinals has decided that the Conclave will begin on Tuesday, 12 March 2013," said a statement sent by the Vatican press office. "A pro eligendo Romano Pontifice Mass will be celebrated in St. Peter's Basilica in the morning. In the afternoon the cardinals will enter into the Conclave."
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