By Rhonda Cook and Mark Davis

Kelly Gissendaner, convicted of murder nearly two decades ago, was put to death early Wednesday morning.

State Department of Corrections officials confirmed that Gissendaner breathed her last at 12:21 a.m. Her final conscious act: singing "Amazing Grace."

"Bless you all," Gissendaner said to an assembly of witnesses. "Tell the Gissendaners I am so, so sorry that an amazing man lost his life because of me. If I could take it all back, I would."

The execution capped a roller-coaster kind of day in which one of Gissendaner's children begged that his mother be spared. An emissary from Pope Francis asked the state Board of Paroles and Pardons to give Gissendaner clemency for masterminding the killing of her husband, Douglas, in 1997. Scores of people turned out in the rain and mist to show support for Gissendaner, too.

But, earlier in the night, the U.S. Supreme Court upheld a decision reached by the 11th Circuit Court of Appeals. The lower court decided to let the state go forward with executing Gissendaner.

A prison spokeswoman said Gissendaner died quietly after saying a prayer.

Gissendaner was ready, said the Rev. Della Bacote. A pastor from Nashville, Tenn., Bacote spent 4  1/2  hours with Gissendaner on her last day alive. "We laughed, we cried, we ate snacks," Bacote said. "We reflected. We prayed.

"She was ready. She was at peace at what was to come, fully accepting of it."

Her execution had been set for 7 p.m. By then, more than 40 people had gathered outside the prison in a show of support for Gissendaner, 47. That number only grew through the evening.

The 7 o'clock hour came, and everyone tensed. Then a rainbow appeared, and everyone relaxed.

"Look!" a middle-aged woman shouted. "That's a rainbow for Kelly!"

The rainbow faded and night fell. Maybe, her supporters said, the delay was a good sign.

"We're not giving up hope, not yet," said Kara Stephens, a former inmate who met Gissendaner when they were sequestered in the same cell block. "Kelly's beat this before."

In her final hours, she hosted visitors. One was Marcus Easley, a retired Chattanooga police officer who's spent years working in prison ministries. He met Gissendaner 15 years ago, and came away convinced that hers was a life worth saving.

"Kelly Gissendaner was praying for us," said Easley.

Three people who did not visit: her children. They chose to make a final appeal to the pardons and parole board instead of visiting her. Brandon Gissendaner, her son, spoke on his mom's behalf. Later, the board announced: the execution would go as planned.

Her execution marks the resumption of capital punishment in Georgia. It also was the first time Georgia has executed a woman since 1945. Hers was the first execution to take place in America since Pope Francis called on Congress to abolish capital punishment, too. He made that plea Thursday, during a six-day visit to this country.

Gissendaner committed her crime in 1997. The facts aren't in dispute: she persuaded her lover, Gregory Owen, to kill her husband. Owen knocked him unconscious, then stabbed him in the neck with a knife repeatedly. This took place in a remote, wooded spot.

She reported him missing the next day. He remained missing for two weeks, until game wardens found his body.

Investigators got busy. They learned that Gissendaner had a boyfriend. Police tracked him down. He confessed and testified against his lover. He got life with the possibility of parole in 2022.

Gissendaner rejected a similar deal and demanded a trial. The jury came back with a death verdict. Since then, she had been in prison. There, said her supporters, she became a Christian, counseling other female inmates in distress. Executing her, they said, would be a travesty.

Douglas Gissendaner's family said keeping her alive is the real travesty. On Monday the dead man's family released a statement damning her.

"As the murderer, she's been given more rights and opportunity over the last 18 years than she ever afforded to Doug who, again, is the victim here," the family wrote. "She had no mercy, gave him no rights, no choices, nor the opportunity to live his life."

Gissendaner's supporters believe in redemption, and they believed in her. By 9 p.m., about 150 people were gathered outside the prison -- a pretty good crowd. This was a famous case: news agencies from across the world were watching the story of the woman who went to prison and found God.

The protesters were in a roped-off area guarded by three police officers in serious-looking riot gear, standing firm as posts. They came singly, in pairs, in crowded minivans. They clustered in a clearing ringed by mature pine trees.

They parted earlier Tuesday night when Kayla Gissendaner, the condemned woman's daughter, appeared briefly. She thanked them for their support, then allowed herself to be taken to a waiting van. She said nothing more. The van's taillights flickered and it was gone.

The rain, intermittent earlier, finally stopped. Mist rose from the ground, crept through the trees. It enveloped those who were holding a vigil in the dark.

Periodically, they broke out in song. A favorite was "Amazing Grace."

(c)2015 The Atlanta Journal-Constitution (Atlanta, Ga.)