Secrets of the papal conclave

(CBS News) 115 Catholic cardinals in Rome are expected to cast their first ballots Tuesday in an election to chose the next pope -- they will likely vote once on the first day of the conclave and and then four times each day until one man garners the required 77 votes to win.

Father Thomas Rosica, the deputy spokesperson for the Vatican, joined the cardinals for Mass in St. Peter's Basilica in Vatican City on Tuesday morning, and told "CBS This Morning" about the "homily of encouragement" delivered to the cardinals at the mass, reiterating "a real call to the mission of what this is all about."

Following the Mass, Father Rosica said the cardinals will eat lunch and have a "little bit of a siesta," before arriving at the Pauline Chapel to begin the "magnificent procession" to the nearby Sistine Chapel, where the conclave is set to take place.

Rosica said the cardinals wear red robes for the procession, not for the sake of ostentation, but because "red is the color of martyrdom."

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"Ultimately, the cardinal is called to lay down his life (for the Church)... Those striking red robes...[are] a reflection of blood," said Rosica.

The cardinals will enter the Sistine Chapel, where they will swear an oath before likely casting their first ballots on Tuesday. They do have the option of delaying the first vote until Wednesday. The swearing of the oath is televised for the public, however the rest of the voting process remains veiled in secrecy.

Rosica said "the secrecy is a great sign of respect" to ensure that "what is happening there is between the cardinals and Almighty God," as well as a sign of respect for those cardinals in the running to become the next pope.

He explained that the votes are cast on small pieces of paper that read in Latin simply, "I elect as Supreme Pontiff:" The cardinals are supposedly asked to disguise their writing before placing their vote in a chalice, all in front of Michelangelo's Last Judgement fresco.

"If you have any ideas of leaking, and you're looking up at the Redeemer and all of the story of redemption, you better think twice," Rosica said, reiterating the solemnity of the conclave location.

"It's more than symbolic, it's frightening... This is not done in a board room, this is done in one of the most holy places" at the Vatican, he said.