Jon Stewart walked away from his role as host of "The Daily Show" only four months ago, but his return to the set Monday night as a guest showed the late night talk veteran's words still carry weight, reports CBS News correspondent Vladimir Duthiers.

Bearded and casually dressed, Stewart returned home, not to check up on the new tenants occupying the house, but to advocate for a cause close to his heart.

"So back in 2010, okay, after far more lobbying than should have ever been necessary, Congress passed what was called the Zadroga Act, funded healthcare for 9/11 first responders who'd gotten sick working at Ground Zero," Stewart explained.

But the health care provision of that bill expired in September.

"It's soon going to be out of money. These first responders, many sick with cancers and pulmonary disease, had to travel at their expense to Washington, D.C., hundreds of times to plead for our government to do the right thing," Stewart said.

The 53-year-old comedian said the 9/11 first responders have been forgotten by the politics of Washington.

"So right now there are 67 senators sponsoring the bill, 260 representatives, which even by stupid Senate and House math is more than enough to do this," Stewart said.

For years, Stewart has been a voice for those impacted by the 2001 terror attacks, providing first responders and their families a set of shoulders to stand on. In 2010, Stewart took up their cause, dedicating an entire show to the issue. But five years later, things are visibly different.

"Just out of curiosity, where is everybody?" Stewart asked first responder Kenny Specht, who was sitting next to three empty chairs.

"Just you and I. Five and a half years ago we did a show. Seventy-five percent of the panel is no longer here. Two of the people have illnesses and John Devlin, who sat at the last chair, an operating engineer, passed away since our show," Specht said. "So I think we brought the statistics to show that when we did the show five and a half years ago, four men sat here. It's you and I."

Specht told Stewart that Senate Majority Leader Mitch McConnell gave him his word during a meeting last week that Congress would fully fund those health care benefits. They said the plan is to attach it to a bill that is set for a vote this week. A spokesman for his office told CBS News: "Everyone, Republican and Democrat, House and Senate, is working very hard to get this done. And it will get done."