Atlanta - As Troy Davis faces his fourth execution date, the effort to save him has come to rival the most celebrated death row campaigns in recent history.
On Monday, the Georgia State Board of Pardons and Paroles will give Mr. Davis what is by all accounts his last chance to avoid death by lethal injection, scheduled for Wednesday.
Whether history will ultimately judge Mr. Davis guilty or innocent, cultural and legal observers will be left to examine why Mr. Davis, convicted of killing a Savannah police officer, Mark MacPhail, 22 years ago, has been catapulted to the forefront of the national conversation when most of the 3,251 other people on death row in the United States have not.
The answer, experts say, can be found in an amalgam of changing death penalty politics, concerns about cracks in the judicial system, the swift power of digital political organizing and, simply, a story with a strong narrative that caught the public’s attention.
“Compelling cases that make us second-guess our justice system have always struck a chord with the American public,” said Benjamin T. Jealous, president of the N.A.A.C.P. “Some are simply more compelling in that they seem to tap deeply into the psyche of this country. A case like this suggests that our justice system is flawed.”
Like others involved in the case, he credits Mr. Davis’s sister, Martina Correia, a media-friendly former soldier who has long argued that the police simply got the wrong man, with keeping the story alive.
And the story has been compelling. A parade of witnesses have recanted since the original trial, and new testimony suggests the prosecution’s main witness might be the killer.
There are racial undertones — Mr. Davis is black and the victim was white — and legal cliffhangers, including a stay in 2008 that came with less than 90 minutes to spare and a Hail Mary pass in 2009 that resulted in a rare Supreme Court decision.
Altogether, it had the makings of a story that has grabbed many armchair lawyers and even the most casual opponent of the death penalty.
The list of people asking that the Georgia parole board offer clemency has grown from the predictable (Jimmy Carter, Archbishop Desmond Tutu, the Indigo Girls) to the surprising, including 51 members of Congress, entertainment heavyweights like Cee Lo Green and death penalty supporters including William S. Sessions, a former F.B.I. director, and Bob Barr, a former member of Congress, and some leaders in the Southern Baptist church. (Unlike some other states, in Georgia the governor cannot commute a death sentence; only the parole board can.)
Propelled by a recent flood of digital media including Twitter traffic and online petition requests, the case has become fodder for discussion in fashionable Atlanta bistros, Harlem street corners and anywhere living room sleuths gather in their search for another Casey Anthony trial to dissect.
On Friday, about 1,000 people marched to Ebenezer Baptist Church here for a prayer vigil, one of hundreds of rallies being organized by Amnesty International around the world.
The facts of the case itself captured the attention of Nancie McDermott, a North Carolina cookbook author who usually spends her time in the kitchen but who took up the cause with a passion once she started reading about it on liberal Web sites.
“I think if my brother or son or dear friend from college were about to be put to death, and there was no physical evidence, and seven of nine witnesses had recanted and testified to coercion in that original testimony, would I shrug and say, ‘The jury made its decision?’ ” she wrote in an e-mail. “I just want people, particularly all the churchgoing people like me, to look me in the eye and tell me, just once, that this is justice.”
There are some larger political themes weaving through the case.
As executions becomes less common and sentences for executions decline — dropping to about 100 a year from three times that in the 1990s — the focus on execution as a means of punishment and a marker of the nation’s cultural and political divide becomes sharper, legal analysts said.
That divide results in a culture that in the same week can generate hundreds of thousands of letters of support for Troy Davis and, conversely, bring a cheering round of applause from the audience at a Republican presidential debate when Gov. Rick Perry of Texas was asked about the 234 executions in his state during his term of office.
“We’ve gotten to a critical point in the death penalty in this country,” said Ferrel Guillory, a professor of journalism and mass communication at the University of North Carolina. “These cases are being phased out but at the same time they don’t make the front page anymore, so when one comes along with a strong narrative and a good advocate, it gets our attention.”
Matthew Poncelet, a Louisiana convict, had Sister Helen Prejean, whose story of her work with him in the final phase of his life brought “dead man walking” into popular lexicon after Hollywood released a film version of the case in 1995.
Mumia Abu-Jamal, the former journalist and Black Panther who was convicted of shooting a white Philadelphia police officer in 1981, rode the power of his own charisma. His case became so popular globally that a road in a Parisian suburb bears his name.
Mr. Davis’s case not only offers a good narrative with strong characters people can relate to — his father was a law enforcement officer, his mother was a churchgoer, his sister is fighting both cancer and for her brother’s innocence — but has also benefited from an explosion in social media.
“Back in 2007, nobody outside of Savannah knew who Troy Davis was,” said Laura Moye, director of Amnesty International U.S.A.’s Death Penalty Abolition Campaign. “Now it’s safe to say over a million people do.”
For proof, she offers the 633,000 petitions she and others delivered to the parole board in an elaborate media event on Friday. About 200,000 of them were electronic signatures gathered by Change.org in less than a week.
“It’s a new era of activism,” she said.
Online organizing drew Anderia Bishop, 37, of Atlanta, to the case last week. She learned about Mr. Davis through an e-mail from ColorOfChange.org, a black political organization.
The fact that there was very little physical evidence and no DNA and a case built largely on witnesses who changed their story got her attention.
“I thought, literally, it could be me, and that’s something a lot of people who are casually watching this case think,” she said. “There are just too many questions.”
But public pressure and intense media attention can cut both ways, said Stephen Bright, president of the Southern Center for Human Rights and a longtime capital defense lawyer.
“It certainly heightens the attention a case gets, but there also can be some defensiveness,” he said. “There has historically been that worry that people from out of state will come in and not understand what really happened.”
The difference, he said, is that in today’s information-rich age, people around the world actually do know most of the facts in the case.
“It tells the State of Georgia that the whole world is watching,” he said.