By Marco R. della Cava

Tommy DeCarloSee how this rock 'n' roll fantasy sounds: One day you're trying to get Home Depot shoppers to apply for in-store credit. The next you're rehearsing with Boston and getting ready for a national summer tour.

"I never could have dreamed this," says Tommy DeCarlo, 43, Boston's new Brad Delp-channeling frontman, who is taking leave from his credit manager job at a Charlotte Home Depot to perform with the band. "That first gig is going to be something."

Bands ranging from AC/DC to Lynyrd Skynyrd have found new singers in the wake of tragedy (Delp committed suicide last year), inevitably choosing road-tested replacements. DeCarlo's rocking Cinderella tale includes the fact that he never has even been in a band.

"I did sing After the Lovin' at my grandparents' 50th wedding anniversary," says the affable DeCarlo, who is married and has two teenagers. "I think they enjoyed it."

All Boston founder Tom Scholz knows is he can't believe his ears. "During rehearsals, it can get downright eerie," he says. "I forget it's not Brad. It makes me feel like someone was at work up there."

In tribute to Delp, DeCarlo posted MP3 files of himself singing Boston over a karaoke soundtrack on his MySpace page. (He had hocked his prized keyboard in 2006 to buy his kids' Christmas gifts.) An impressed visitor to his page urged him to contact Boston management and offered up an old e-mail address. Doubtful but with nothing to lose, DeCarlo sent off a note with a link. Destiny intervened.

"My wife was at her computer playing our tunes, and I asked her whether it was us playing live," Scholz says. "She said, 'It's some guy in North Carolina singing your songs.' I said, 'I know Brad's voice, and that's Brad.' She turned it up, and only when I heard the backing track did I know it wasn't us."

Scholz flew DeCarlo and his family up for an audition, which led to a Delp tribute show and the tour invite. DeCarlo and the band's other new member, Stryper frontman Michael Sweet, will appear on Boston's next album in early 2009.

Finding a new band member online "could happen more and more, because you no longer have to be anywhere specific to audition," says Howard Kramer, curatorial director of the Rock and Roll Hall of Fame and Museum. "Journey just found their new lead singer (Arnel Pineda) in a Filipino cover band that put their stuff on YouTube."

Even if DeCarlo's Boston idyll proves short-lived, he's unlikely to forget this summer. His colleagues won't let him.

"It's like we've got our own American Idol winner right here in our store," says DeCarlo's manager, Mark Ortiz. "When he plays nearby, we'll all be there, orange aprons on."