VATICAN CITY - Storm clouds gathered over St. Peter's Basilica today, almost as if God Himself wanted a somber setting for a somber day in the history of the Catholic Church.

Inside, all of the 115 cardinals and, symbolically, all the faithful, gathered for one last mass. A reminder amid the mighty spaces of St. Peter's that this papal election, in the belief of the Catholics, is a kind of worship, a kind of prayer to pick the next pope.

In the homily was a call for unity from the dean of the College of Cardinals, Angelo Sodano, who also praised the man who was not there: Benedict the Pope Emeritus, now in solitude outside of Rome.

Among the men who will make this conclave vote was Cardinal Justin Rigali, the former archbishop of Philadelphia. This will be his second conclave - he voted in Benedict's election back in 2005 - so this time, Cardinal Rigali knew what to expect.

"It begins by singing in Latin to bring the Holy Spirit and this is the oath that is taken," he said.

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The cardinals read the secrecy oath together. Rigali has been there before. He has taken the same oath and shouldered the same historic task. He recalled what it was like to be inside the Sistine Chapel during that moment.

"It's not just a question of talking or trying to make it into something political," he said. "It's a fact that the people of God are asking God to raise up a man that will remain with his human limitations and will be a worthy leader of the church. So that is what we are asking."

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Rigali's journey to Rome began nearly two weeks ago from the small city of Knoxville, Tenn., where he has retired. Amid the faithful of Knoxville, a public prayer service was held in his honor, with 1,000 local Catholic high school students and community members in the pews. At the airport he was cheered like a rock star as he headed to his plane.

At a layover in Atlanta, I met up with him.

Next stop: Rome.

After arriving, I asked him if he knew yet in his heart and mind whom he would vote for in the conclave.

"This is a very serious election that involved listening," Rigali said. "It involves weighing different candidates and this cannot be done a priori. It can't be done before you go in and you decide. You have to be open to the process that is taking place and we believe the Holy Spirit is with us."

Last week, Rigali joined the other cardinals to say farewell to Pope Benedict XVI, and then they got down to the real work here: Meetings and more meetings, where the politics happen - and in coffee breaks too.

"The coffee breaks are a component," Rigali said. "It gives us the opportunities to speak with the cardinals, some we know more, some we know less. It gives us the opportunity to exchange our thoughts."

But this was a different reality today - a deeper reality, they believe. After their oath, after their prayers, the simple command was said: "Extra Omnes," which means "outside all," or colloquially, everybody out who is not a cardinal elector.

And they left. The staff, the priests, the cameras. The great doors to the Sistine Chapel were closed and the cardinals were alone inside.

Cardinal Rigali described the voting as a kind of fellowship in prayer.

"People are trying to listen to the inspiration of the Holy Spirit," he said. "We are trying to hear the wisdom that is communicated in their brother cardinals."

As a cold, damp evening fell on the Eternal City, thousands waited in St. Peter's Square, straining to see the chimney atop the Sistine Chapel for the smoke that signifies a vote has been taken.

Suddenly, at precisely 7:42 p.m. local time, there it was.

Black smoke. An inconclusive vote.

There is no pope. Tonight.