A crowded field and Republican voters’ reluctance to pick one frontrunner and stick with him or her has forced GOP presidential candidates to sell themselves in several primary debates. Texas Gov. Rick Perry, who stormed into the race on a high just three months ago, has been falling ever since, largely because of his weak performance debates. In fact, they’ve been so bad that he briefly flirted with the idea of not participating in some of them.

Wednesday night’s big gaffe during the debate on the economy hosted by CNBC in Michigan may have him rethinking his decision. Part of Perry’s stump speech is a plan to eliminate the Commerce, Education and Energy departments if elected president. But when trying to name the three, he stumbled and could only come up with two, which made everyone in the room feel awkward.

“And I will tell you, it’s three agencies of government, when I get there, that are gone:  Commerce, Education and the — what’s the third one there? — let’s see,” he said.

After struggling for several seconds, he said, “I would do away with the Education, the Commerce and — let’s see — I can’t. The third one, I can’t. Sorry. Oops.”

He remembered later in the debate that Education was the agency he was searching for, and after the forum acknowledged that he’d “stepped in it.”

Herman Cain has performed pretty well during past matches and has been careful to not offend anyone. But Wednesday night, when referring to a Republican health care plan offered when California Democrat Nancy Pelosi ruled the House, he said, “We didn't hear about it in the previous Congress because 'Princess Nancy' sent to it committee and it stayed there. It never came out."

According to a CBS report, several journalists noted on twitter that calling her that wasn’t such a wise move for someone facing serious allegations about how he’s treated women.

"That was a statement that I probably shouldn't have made, but I was trying to make a point," Cain said in an interview with CNBC after the debate.

(Photo: Justin Sullivan/Getty Images)