"It could be massive. We're both looking for something to do, right?"
He accuses Cruz of flip-flopping on "ethanol, immigration, H-1B visas."
The video takes several shots at rival Ted Cruz.
Iowa's caucuses are one week from Monday.
Huckabee's attack follows Cruz's criticism of "New York values."
He said Obama is wrong in suggesting it is easier to buy a gun than groceries.
"If we slay the dragon, what dragon do they continue to fight?" Huckabee asked.
Christie rises, Carson falls in latest rankings by The Hill.
Huckabee says Trump won't hurt his chances in 2016 by publicly attacking the Clintons.
The White House hopeful said there is a "seething rage" among GOP voters.
"We're moving forward," Huckabee insisted.
The deal came after Trump triggered equal opportunity rules with his "SNL" appearance.
Huckabee called Obama's stance on admitting Muslim refugees "a disaster."
The two will take part in the undercard debate before going to Trump's event.
"I'll be happy to take it," the White House hopeful added.
Trump and Cruz are skeptical of the science behind climate change.
So far, only a few Republican presidential candidates back Obama's agreement.
Trump gets 31 percent, Cruz 29 percent in Quinnipiac poll.
Alice Stewart left Huckabee's campaign last month.
"Richard Nixon resigned for less than this," the GOP presidential candidate says.
Huckabee was asked if the ad was selectively edited.
Ayla Brown is a former "American Idol" contestant.
Huckabee's communications director has left his campaign.
"I fear he may have made things worse," Sen. Marco Rubio said.