The US state of Virginia is set to execute by lethal injection a 41-year-old grandmother, the first woman to be put to death in Virginia in almost 100 years.
The US supreme court late on Tuesday rejected a last-minute reprieve for Teresa Lewis, who will receive a lethal injection at 0100 GMT on Friday morning.
The court said in its brief ruling that the stay of execution requested by Lewis "is denied".
Abolitionists paint Lewis as an example of why capital punishment is flawed, saying she has diminished mental faculties and was taken advantage of by smarter accomplices.
But with an IQ of about 70 or above, Lewis is considered fit for trial in the southern state of Virginia and she pleaded guilty to hiring two men in 2002 to murder her husband and stepson to pocket their $350,000 life insurance policy.
Adding to the supreme court's decision, Bob McDonnell, the Virginia governor, has said he will not intervene to stop the execution, seeming to remove all final chances for a reprieve.
"After numerous evaluations, no medical professional has concluded that Teresa Lewis meets the medical or statutory definition of mentally retarded," he said in a statement.
He said he could find "no compelling reason to set aside the sentence that was imposed by the Circuit Court and affirmed by all reviewing courts".
Lewis met Rodney Fuller and Matthew Shallenberger in a Walmart superstore. Soon she began an affair with the 22-year-old Shallenberger and encouraged her 16-year-old daughter to get together with Fuller, who was 19.
Lewis admits she left the door of the family trailer in rural Pittsylvania County open in 2002 so the two young accomplices could enter and shoot her husband and his 25-year-old son, who was in the military.
All three pleaded guilty. The triggermen got life in prison, but Lewis, who was deemed fit to stand trial, was sentenced to death as the mastermind of the killings.
But Lewis's supporters offer a different picture of a borderline mentally disabled woman, who has struggled with a behavioral dependency disorder and was addicted to prescription drugs.
And they further question why she should be executed when the two men who actually carried out the murder were handed life without parole.
Lewis's case made global headlines on Tuesday when Mahmoud Ahmadinejad, the Iranian president, contrasted the lack of protest over her impending execution to the "storm" surrounding a woman sentenced to be stoned in Iran.
"A woman is being executed in the United States for murder but nobody protests against it," Ahmadinejad told a group of Islamic figures in the US on Monday, according to IRNA, Iran's official news agency.
Iran has been under international pressure to spare the life of Sakineh Mohammadi Ashtiani, a 43-year-old mother who was sentenced to death by stoning for adultery in 2006.
Lewis's lawyers argue that new evidence, including her low IQ, has appeared since her trial that should prevent her execution.
The key piece of evidence they wanted considered was a letter from Shallenberger, who killed himself in jail in 2006, in which he claims full responsibility for the murder plot and suggests he pushed Lewis into it.
"From the moment I met her I knew she was someone who could be easily manipulated," he allegedly wrote. "Killing Julian and Charles Lewis was entirely my idea. I needed money, and Teresa was an easy target."
Lewis will become only the 12th woman to be executed in the US since the death penalty was reintroduced in 1976. In that time 1,215 people have been executed.
The US is among the countries that execute the most people each year, along with China, Iran, and Saudi Arabia.