Homeless at 19 and working as a West Virginia car-washer to provide for his family just prior to competing on the show, Murphy, now 37, says becoming an overnight star is surreal.
"It's beyond belief," the Frank Sinatra-sound-alike jazz singer told PEOPLE alongside his teary-eyed wife on Wednesday night shortly after winning $1 million and his own headlining act in Las Vegas. "Is this really happening? I'm standing on a red carpet taking pictures. It feels wonderful."
As well it should. "I started off as a toddler dancing for my family and friends," said Murphy. "It's been a hard journey trying to get to this point."
Murphy, who kicks off his Vegas show on Oct. 28, wants his victory to be an inspiration to others.
"I want to place hope back into [society], because it's like people have lost hope in their dreams and desires," he said. "I want to reverse that."
Although Murphy now has the finances to party like a rock star, he sure isn't celebrating like one.
"I'm getting a lot of sleep," he said of his plans for the rest of the evening, despite being invited to sip bubbly with his idol and Wednesday night duet partner, Patti LaBelle. "I've got to get some sleep."