(VATICAN CITY) -- A new pope could be elected Tuesday as the 115 Roman Catholic cardinals enter the Sistine Chapel for the conclave that will select the next pontiff.
The first vote is set to take place Tuesday evening in Rome (afternoon ET), although it is unlikely that on the first ballot any candidate earns the two-thirds majority needed for election. If no pope is elected on Tuesday evening's vote, the 115 cardinal electors will resume the conclave on Wednesday.
On Tuesday morning, the cardinals celebrated a mass in a packed St. Peter's Basilica with a homily from Cardinal Angelo Sodano, dean of the college of cardinals.
"We implore the Lord that through the pastoral solicitude of the cardinal fathers, He may soon grant another good shepherd to his holy church," Sodano said.
When Sodano praised the retired Pope Emeritus Benedict XVI as a "beloved and venerable" pontiff, cardinals responded with a lengthy applause.
In recent days, cardinals have expressed optimism that the conclave will be a quick one and a new leader of the church's 1.2 billion followers will be swiftly selected. The start of Holy Week on March 24 gives the conclave an added sense of urgency.
"In a few days we will have a new holy father," Cardinal Christoph Schoenborn of Austria said on Sunday.
When the cardinal electors -- only cardinals under 80 can vote -- enter the conclave, they will be shut off from the outside world: no television, Internet or newspapers. Electronic jamming devices have been installed in the chapel.
The cardinal electors Tuesday morning moved into Santa Marta, the house where they will reside during the conclave. Later in the day, they will gather in the Pauline Chapel before proceeding into the Sistine Chapel, where the doors will then be locked.
After each session of voting, the ballots are burned and smoke is emitted from the chapel's chimney, with black smoke signaling that no candidate has been elected in the preceding rounds of votes and white smoke indicating a new pope has been picked.
The first smoke can be seen between 1 p.m. and 3 p.m. ET on Tuesday.
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