With just months to live, one Denver man is doing everything he can to gain access to an unapproved cancer drug.

Nick Auden, 40, was diagnosed with stage 4 melanoma in September 2011. Two years of radiation and experimental treatments later, the father of three is still alive, but doctors say time is running out, ABC News reports.

"Some people survive, 90-odd percent don't," he said. "There's no doubt that was tough news. I had trouble not being emotional about it every time I thought of the concept of not being there to watch the kids grow up."

So when Auden heard of a clinical trial for a "wonder drug" able to help a person's immune system shrink tumors permanently, he immediately signed up.

Just hours into the trial, however, Auden suffered a complication and was disqualified.

That night, Auden's wife Amy lay awake, struggling to come to terms with what had just happened.

"I could not sleep," she said. "I was lying awake at night thinking, I can't just lie here and do nothing."

Before the night was over the "Save Locky's Dad" campaign was born, featuring their 7-year-old son Lachlan, nicknamed Locky.

"I want my dad to get the PD-1 drug because then I can do the things I like to do with him all the time," Locky says in the video. Meanwhile, Locky is seen playing frisbee with his dad.

The Audens don't want money -- just petitions. And it seems to be working: a Change.org petition has more than 240,000 signatures and counting.

"I can't imagine life without Nick. I can't imagine telling Locky he has to watch the big game alone, telling Hayley that Daddy can't take her bike-riding anymore, or knowing that my youngest son won't even remember his dad," Amy writes on the petition's site. "I can't live with that possibility and I won't. I will never stop fighting to save my husband."