"Look at his high unfavorable ratings," host David Gregory said. "At 50%. The highest of any candidate running in recent memory. This is an image problem that his philosophical statements in this speech in May to fundraisers only exacerbates."

Brooks did not mince words, calling Romney "the least popular candidate in history."

"He has to look at what the president's weakness is," Brooks said. "He's never gonna win a popularity contest. As you said, he's the least popular candidate in history."

Brooks added that Romney "does not have the passion for the stuff he’s talking about."

"He’s a problem solver," Brooks said. "I think he’s a non-ideological person running in an extremely ideological age, and he’s faking it."

Polls have brought grim results surrounding Romney's favorability, with a late August ABC News/Washington Post survey drawing a 35 percent likability rating.