At Thursday's debate in Iowa - the last before voters in the state vote Jan. 3 - Perry said that, like the Denver Broncos quarterback, he's been underestimated.
Perry has struggled in the debates, and in one he paused awkwardly, unable to remember the third federal agency he would dismantle if elected.
But he said Thursday night he's, in his words, "kind of getting to where I like these debates."
Perry said if he becomes the GOP nominee, he and Democratic President Barack Obama "will get it on."