"Real Time," which debuted in 2003, had a wide range of guests from civil rights activist Jesse Jackson to conservative writer Ann Coulter, the New York Post reported. Maher said conservative guests have not been as willing as liberals to come on his show.
"I don't blame conservative guests for not wanting to come on," Maher said. "They complain the audience is stacked against them, but they know that from the get-go."
Maher's source of humor is politics and current events. His father used to work in the news business in New York.
"News is a great wellspring of material," he said. "For me, I never thought there was anything better than the news ... . It's always changing."
But Maher has missed his soapbox since the end of the show's most recent season.
"When movie stars are getting pulled over and they start spouting anti-Semitic rants, it's a tough day to be on the sidelines," Maher said.