Jon Stewart couldn't believe Mitt Romney missed a chance to hammer Newt Gingrich at the last GOP debate.

On Monday night, The Daily Show host thought Romney had many answers to choose from on what he disagreed with the former House Speaker over, listing some of them to his audience.

"I would not have taken the $1.6 million that Gingrich took from Freddie Mac while being a historian while the housing bubble was going on," he suggested. "Or I never had to play $300, 000 to settle Congressional ethics changes. Or I never had to shut down the government based on a suboptimial Air Force seating assessment. Or, I never menaced Manhattan until I was defeated by three comic geniuses and Ernie Hudson."

But instead of all those perfectly valid arguments, Romney instead chose to assert that, unlike Gingrich, he would not create a lunar colony to get minerals from the moon -- leaving Stewart in disbelief.

"What, what, you start with the lunar mines idea?" he asked. "Newt Gingrich is a life support system for bad ideas, and you magically reach out and pick his one good idea?"

WATCH: Video from Comedy Central, which was broadcast on December 13, 2011.