By Ralph Ellis

(CNN) -- A Georgia man, scheduled to die at 7 p.m. Tuesday, would be the first inmate in the United States put to death since the botched execution of an Oklahoma man in April.

Lawyers for Marcus A. Wellons, 59, are filing a series of last-minute appeals to stop the execution.

The Georgia Supreme Court denied Wellons' motion to intervene in the appeal of Warren Lee Hill, another inmate on Georgia's death row.

Wellons was convicted in 1993 of raping and killing India Roberts, 15, in Cobb County, just outside Atlanta. Wellons is scheduled to be put to death by lethal injection at the Georgia Diagnostic and Classification Prison in Jackson.

The Death Penalty Information Center said the execution of Wellons would be the first in the United States since Clayton Lockett was put to death in April in Oklahoma.

Execution witnesses said Lockett, a convicted murderer and rapist, convulsed and writhed on the execution gurney and struggled to speak, before officials blocked the witnesses' view.

Lockett died of a heart attack 43 minutes after being administered the first drug, CNN affiliate KFOR-TV in Oklahoma City reported.

A team that prepared Lockett for execution in April failed to set a properly functioning I-V in his leg, according to preliminary findings of an independent autopsy released last week.

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