Tomorrow marks a big day for one truly big-hearted pup: The winner of the 2012 American Humane Association Hero Dog Awards will be crowned at the Beverly Hilton Hotel in Los Angeles.

The black-tie, star-studded event — everyone from Betty White to Jewel will be in attendance — is designed to honor the many amazing canines who make a difference in the lives of countless people, ranging from therapy pups to search-and-rescue dogs.

This year eight dogs are vying for the top title, and Vetstreet caught up with the handlers and owners of four of the heroic canine contenders.

Hero Dog Gabe with his owner Chuck

Gabe, the Military Veteran

Although he's now retired, this Labrador Retriever completed more than 210 combat missions in Iraq, and successfully sniffed out 26 explosives and weapons finds, earning him three Army Commendation Medals.

“We were deemed the most productive military dog team in the theater of Iraq in 2007,” says Gabe’s former military-handler-turned-owner Sergeant First Class Charles Shuck. “When soldiers died in Iraq, Gabe (shown at left) would represent a piece of home as grieving soldiers would hug him and cry on him. He gets the chance to be the voice of all military working dogs.”

Hero Dog, Stella

Stella, the Therapy Poodle

In the span of just eight months, Marissa Levy had lost her father, her best friend and her dog. But once she adopted a Standard Poodle puppy, whom she named Stella Lenore in honor of her grandmother, Levy’s life began to brighten and have a compassion-filled purpose.

“I was at a dog park with Stella, who was about five months old, when a lady told me that my dog was exceptional and then asked if she was in training to be a service or therapy dog,” recalls Levy. “When Stella turned one, I enrolled her in the Therapy Dogs International program, and she breezed through. Today, we make therapy visits six days a week, and she seems to bring out the best in people — the staff at one nursing home told me that a man who had never spoken now has conversations with Stella but no one else."

Hero Dog, Daniel

Daniel, the Miracle Survivor

Like far too many shelter animals, this Beagle mix was set to be euthanized in an Alabama gas chamber with 17 other dogs last October. But Daniel did the impossible: He emerged alive, and was eventually adopted by Joe Dwyer, a motivational speaker based in New Jersey.

"It is nothing short of a miracle that he survived the gas chamber," says Dwyer, who's now spearheading Daniel's Law, which would ban the use of gas chambers in 30 states that still use the inhumane method. "Far too many animals waiting in shelters are like Daniel (shown above) — loving, energetic and young. They do not deserve to die. They deserve good homes."

The duo is involved in other good works too: They've devoted the past year to educating the public about the importance of spaying and neutering, as well as adopting shelter animals.

Hero Dog, Tabitha

Tabitha, the Diligent Student

When Anne Drake received her master’s degree diploma in social work during graduation ceremonies at Indiana University’s South Bend campus, the crowd erupted in applause because Drake, who gradually lost her sight as an adult, was led by her then guide dog, Tabitha, a German Shepherd Dog sporting a canine-sized cap and gown.

“The chancellor also announced Tabitha’s name, and even shook her paw,” says Drake, who relied on Tabby to navigate the campus for over six years before the dog was retired and returned to her original puppy raiser.

For more on the 2012 American Humane Association Hero Dog Awards contenders, tune in to the Hallmark Channel for a 90-minute special that will air on Nov. 8 at 8 P.M. ET/PT.