"Bring him home."

As Ruby Ridpath typed those words into an email in November 2011, she committed to providing permanent housing for a combat veteran. A furry, four-legged combat veteran.

She couldn't help herself. From the minute she laid eyes on a picture of Carlos - a platinum-blond yellow Labrador retriever who had spent most of his life sniffing for explosives in Iraq and Afghanistan - Ridpath was smitten.

"It didn't matter what the breed was," she tearfully recalled of the night she and her husband saw his picture for the first time, emailed to them from a Peterson Air Force Base airman and dog enthusiast stationed in Kabul, Afghanistan.

"We just knew we wanted to bring home a veteran."

Carlos' future was uncertain, the airman said via email.

The four-legged warrior had spent 21/2 years protecting members of the Army's 3rd and 4th infantry divisions from insurgents' explosives in Baghdad and two more years doing the same for Special Forces soldiers in Kandahar, Afghanistan.

But he wasn't technically a military working dog. He was a contract working dog, owned by a private company.

Though contract working dogs perform the same tasks as military working dogs, they're not always treated the same. Some don't receive proper medical care or placement with an adoptive family after retirement, Ridpath said.

If someone didn't pay his way back to U.S. soil, Carlos' company might turn him loose, the airman explained to Ridpath in the November email.

So the Ridpaths paid for Carlos' flight home. They picked him up Nov. 13, 2011, at the Colorado Springs Airport.

Now the Ridpaths have nominated Carlos for the 2013 American Humane Association Hero Dog Awards - in the military dog category.

Though Carlos wasn't a military dog, he performed the same duties and saved countless lives, said Ridpath, who is hoping that Carlos' story draws awareness to the plight of contract working dogs.

"They work alongside each other, performing the same job," said Ridpath, a board member for Military Working Dog Adoptions, a charity that helps match retired dogs with adoptive parents.

"Do you think any of the troops ask if the dog who saved them was a military working dog or contract working dogs? They don't care. They're heroes."