Glossip maintained his innocence Tuesday in a brief telephone interview with The Associated Press and said he remains optimistic that his lethal injection will be halted.
“They'll never take that from me,” Glossip said. “I'll hope for the best. I won't let it bring me down.
“If you've got to go out … you don't want to be bitter and angry about it.”
Glossip's case has drawn attention from death penalty opponents, and his family and supporters rallied Tuesday at the Oklahoma Capitol. They want Republican Gov. Mary Fallin to issue a 60-day stay to give Glossip's attorneys more time to investigate new leads.
But the governor said in a statement Wednesday that she remains convinced of Glossip's guilt, and “after carefully reviewing the facts of this case multiple times” has no plans to issue a stay.
Among his supporters is Hollywood actress Susan Sarandon, who played a nun in the movie “Dead Man Walking.” The woman Sarandon portrayed, anti-death penalty advocate Sister Helen Prejean, serves as Glossip's spiritual adviser and plans to attend his execution Wednesday.
“Anytime a human being is killed, it’s the worst of the worst. [The executed inmates] are all unique universes that are being destroyed,” Prejean told Al Jazeera in a previous interview.
Oklahoma County District Attorney David Prater, whose office prosecuted Glossip before Prater was elected, said he's reviewed boxes of evidence and is convinced of Glossip's guilt.
“Mr. Van Treese would not be dead but for Mr. Glossip offering what Mr. Sneed thought was half of $10,000 to kill Barry Van Treese,” Prater said. “[Glossip] set everything into motion.”
Van Treese's wife, Donna, wrote in a letter to Oklahoma's Pardon and Parole Board last year that the loss of her husband has been devastating to her and her family.
“As the wife, I lost the most important person to me: my husband and the father to my children,” Donna Van Treese wrote. “I have had a very hard time just moving on one day at a time, and physically I have been under more stress than any one person should endure in a lifetime.”
Glossip's execution is scheduled for 3 p.m. local time on Wednesday. Department of Corrections spokeswoman Terri Watkins said the time was moved from 6 p.m. so the process didn't disrupt a shift change and meal time at the facility, and so that media and execution witnesses would be off the prison grounds before dark.
Al Jazeera and wire services