Pike and her boyfriend were convicted in the 1995 killing of 19-year-old Colleen Slemmer, their classmate at Knoxville Job Corps.
Pike's lawyers have filed a clemency petition seeking to commute her sentence ahead of the September 30 execution date.
Prosecutors said Pike feared Slemmer was a romantic rival and lured her to a secluded area where she and her boyfriend tortured and killed Slemmer. The case received widespread attention because of the brutality of the killing, the ages of the people involved and because a satanic symbol was carved into the victim's body.
Pike does not deny her guilt, but her lawyers and supporters argue a death sentence is not appropriate for a crime committed at 18 with untreated mental illness after a childhood of brutal sexual abuse and neglect.
Slemmer's mother wants the lethal injection go forward, saying she has waited decades to see Pike's sentence carried out.
Tennessee Governor Bill Lee announced he would not grant clemency. Pike's lawyers have asked the Supreme Court to stay the execution.
Pike's lawyers said she experienced an exceptionally traumatic and abusive childhood.
Assistant Federal Defender Stephen Ferrell said Pike was sexually abused starting from when she was a toddler and that she was raped at ages 11 and 17.
He said Pike's lawyers at the penalty phase of her trial did not present the jury with what he said was critical information about her past or argue that her age should be a consideration.
Pike was later diagnosed with bipolar disorder and post-traumatic stress disorder.
"I was a mentally ill 18-year-old kid. It took me numerous years to even realise the gravity of what I'd done. Even more to accept how many lives I affected. I took the life of someone's child, sister, friend. It sickens me now to think I had the ability to commit such a crime," Pike said in a statement included in her clemency petition.
In the modern death penalty era, Ferrell said, other 18-year-olds who were sentenced to death in Tennessee have since had their sentences reduced.
If Pike's execution proceeds as scheduled, it would be Tennessee's first execution of a woman since 1820, Robin M. Maher, executive director of the Death Penalty Information Center, said.
Executions of female inmates are also rare in the US. Since 1976, 18 women have been executed in the country, representing about one per cent of all executions, according to the centre.
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