RICHMOND -- The time has come when Joseph M. Giarratano is literally counting the hours left.

His may number less than 140, and the man at the center of Virginia's most publicized death penalty case says he is spending nearly all of them awake -- answering mail, giving interviews, unable to sleep as he contemplates the two-minute-long jolts of electricity that are to take his life during an execution scheduled for Friday.

"I am not an abstract issue," Giarratano said. "I am a living, breathing individual who will fry."

Just a mile from where Giarratano sits as the lone inmate in the otherwise deserted state penitentiary housing Virginia's electric chair is the office of the only man who can save his life, Gov. L. Douglas Wilder.

Two cardboard boxes sit in the corner of Wilder's office, filled with the legal facts of a case that has come to symbolize the death penalty debate because of new doubts that Giarratano committed the murders for which he was sentenced in 1979 and because of his transformation in prison from drug addict to legal scholar and writer.

Aides to Wilder say the case has generated thousands of calls and letters, far more than any other issue Wilder has confronted, nearly all in support of clemency.

In Richmond, there have been rallies and television commercials urging Wilder to grant a conditional pardon, which Giarratano's attorneys say would clear the way for a new trial. CBS's "48 Hours," among dozens of national and international news organizations, is reporting on the case. Giarratano supporters who have appealed to Wilder include not only liberals such as George McGovern and actor Mike Farrell, but prominent conservatives and death penalty advocates such as columnist James J. Kilpatrick.

Wilder has the power to pardon Giarratano or to commute the death sentence to life imprisonment. Giarratano has offered to submit to a new trial if a pardon is granted; a pardon would rescind the judge's finding of guilt, and Giarratano would waive his right to protection against double jeopardy. That would be unprecedented in Virginia, and Wilder's staff is studying whether the state constitution provides that option.

Wilder has given no hint of what his actions will be.

One factor adding political pressure to the case is that Wilder has been petitioned by about 20 legislators to stop the execution. Giarratano's is believed to be the first execution in recent times scheduled to take place while the General Assembly is in session.

The long and complicated story began 12 years ago with the slayings of a 15-year-old Norfolk girl and her 44-year-old mother.

For Giarratano, now a bearded, stocky man of 33, the stakes are life or death. For Wilder, who has designs on national office, the stakes may be his political future.

Wilder is a former death penalty opponent who publicly changed his position on that issue in the early 1980s. In his first 13 months as governor, he has not intervened in the executions of three other convicted murderers.

Having demonstrated that he isn't squeamish about implementing the death penalty, one argument goes, Wilder is less vulnerable to soft-on-crime criticism from conservatives if he keeps Giarratano out of the electric chair.

"The case has developed in such a way that Wilder could politically defend any decision he chooses to make," said Robert Holsworth, a political scientist at Virginia Commonwealth University.

Wilder dismissed as "right crass" the suggestion that politics colors his thinking.

But Giarratano said he knows that decisions about his fate do not occur in a political vacuum. "That's the way the death penalty works in this country," he said. "It's really scary that politics could ultimately decide my fate."

Virginia has 45 people on death row. Since the constitutionality of the death penalty was reestablished, 11 people have been executed in Virginia, the first of them under Gov. Charles S. Robb in 1982. The District does not have the death penalty. Although it is technically on the books in Maryland, no one has been executed there since 1961.

Lately, the pace of executions in Virginia has quickened, as appeals are exhausted in cases that have been dragging through the courts for years. In a little more than a year, Wilder has had to weigh as many cases as his predecessor, Gerald L. Baliles, dealt with in the first three years of his term.

The fourth convicted murderer to come before Wilder is Giarratano. He says his only recollection of the crime came when he awoke from a drug-induced stupor on Feb. 4, 1979, to find his two roommates dead in their Norfolk apartment.

Toni Kline was lying in a pool of blood in the bathroom. Her daughter, Michelle, was in her room on the bed, where she had been beaten and possibly raped.

Convinced that he was responsible, Giarratano, then a 21-year-old scallop boat worker, fled by bus to Jacksonville, Fla. It was there he surrendered and gave the first of five confessions that were the cornerstone of the prosecution's case.

After a half-day trial, Circuit Judge Thomas R. McNamara sentenced him to die. Eager to end a life that he considered a failure, Giarratano initially did not contest the execution order.

In 1981, Giarratano sat in the same Richmond cell where he sits now, less than 24 hours from the electric chair. The execution was stopped after Giarratano was ruled mentally incompetent to waive his right of appeal because of his addiction to a tranquilizer administered by prison doctors.

It was back at the Mecklenburg Correctional Center in rural Southside Virginia, finally off all drugs, that an evolution began for Giarratano that his supporters say has been nothing short of astonishing. Infused with a desire to live, Giarratano immersed himself in the law, not only on behalf of himself but on behalf of other inmates.

Giarratano's bid to guarantee the right of death row inmates to state-funded counsel reached the U.S. Supreme Court, although he ultimately lost. Giarratano has written an article in opposition to the death penalty that will appear in the next issue of the Yale Law Journal.

It was also during this time that the members of Giarratano's new defense team -- he has criticism for his first lawyer -- started to try to pick apart the prosecution's case, finding holes they say would lead to a reasonable doubt at a new trial.

Richmond lawyer Gerald T. Zerkin has raised these issues:

Forensic experts believe Toni Kline was stabbed by a right-handed assailant, but Giarratano is left-handed.

A bloody bootprint found near Toni Kline's body did not match Giarratano's boots. Although Kline's murder was exceptionally bloody, no blood was found on Giarratano's clothes or body when he turned himself in.

Private investigators have come up with other possible suspects, including a friend of Toni Kline's with a history of violence and sexual abuse.

No weapon was ever found. Giarratano told investigators he threw the knife he used into the back yard of the Kline home.

On appeal, state and federal courts ruled that this information was not compelling or was coming too late to justify a new trial. Virginia Attorney General Mary Sue Terry, who is preparing to run for governor in 1993, has fought vigorously against a new trial for Giarratano, and her media spokesman dismissed Zerkin's arguments as "old evidence in a new wrapper."

Earlier this month, Giarratano was moved from Mecklenburg to the Richmond prison. The facility was shut down in December except for the execution chamber, which won't be moved for two months. Giarratano sits in the aging penitentiary as its last inmate.

"It is a terrible thing that is about to be done," columnist Kilpatrick wrote in a recent column, in which he said that after "hours of brooding over the record," he was "filled with reasonable doubts" about Giarratano's guilt.

The death penalty is popular among the electorate at large, but is opposed by many liberals who have a disproportionate impact in the Democrats' national nominating process. New York Gov. Mario M. Cuomo, a potential rival of Wilder's if they both seek the Democratic presidential nomination, is a staunch opponent of the death penalty.

"If Wilder doesn't intervene . . . it would be a horrible commentary on Virginia, on politics, on 'Willie Hortonism,' " said Alvin Bronstein, head of the American Civil Liberties Union's National Prison Project.

Mike Farrell, who starred on television's "M*A*S*H" and has befriended Giarratano, said many in Hollywood's political community -- traditionally a large source of campaign money in Democratic politics -- are watching the case.

"The governor can be an instrument of justice," he said. "I think if he chooses to go the other way, there will be a lot of people who will be very disappointed to see, 'Here's another pragmatist.' "

For his part, Giarratano said he is resigned to waiting, hoping that Wilder will be persuaded by the letters he sent him.

"I told him I wasn't asking for mercy, I was asking for justice," he said. "He's my only hope."