Des Moines, Iowa — Senator Cory Gardner (R., Colo.) is cracking up.

On the movie theater screen in front of him looms Donald Trump, his face scaled to the size of a small car, lips pursed as he explains why he has lately taken to arguing that Ted Cruz might not be eligible to be president because he was born in Canada.

When Marco Rubio cuts into the exchange between Cruz and Trump, declaring, “I hate to interrupt this episode of Court TV,” the 90 or so attendees assembled here at Flix Brewhouse for the Rubio campaign’s debate-watching party go wild.

But no one is more enthusiastic than Gardner, who flew in from the GOP policy retreat in Baltimore to stump for Rubio over the next few days alongside South Dakota representative Kristi Noem. No one seems to be enjoying himself more, either.

Over the course of more than two hours, Gardner, sitting in the center seat in the center row of the theater, leans forward, intently watching the screen, the shadow of a smile fixed on his face. When an entertaining exchange happens, he sits back in his chair and strokes his chin, and the smile grows even bigger. He laughs heartily at the dust-up between Trump and Cruz. He claps ardently when Rubio makes a good point. He even smiles at the insults, breaking out into a grin when Bush refers to Rubio and Cruz as “backbench senators.” During a 15-minute interview with National Review, he pauses several times to refocus his attention on the screen. The first time, he listens to Rubio talk about the Second Amendment, applauding vigorously. The second time, he gives his attention to Cruz. “‘Miss America,’ ‘guns,’ and ‘rounding them up’ in the same sentence,” Gardner remarks in joking disbelief.

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“I love this. . . . It’s sick, I love this stuff,” Gardner will laugh to reporters afterward. “This is fun. It really is.”

About halfway through the debate, Noem slips in beside Gardner, having suffered flight delays. “Delta and I have a love-hate relationship,” she cracks.

The two spend the rest of the debate with their heads tilted together, chatting and laughing as the GOP contenders duel on the screen.

#share#Rubio finds himself in a polling no-man’s land in Iowa. He is decidedly behind Cruz and Trump, who have dominated polls for the past couple of months, but noticeably ahead of the rest of the field, which continues to languish in the single digits. Noem, 44, and Gardner, 41, both young, attractive members of Congress, embody the generational change that is such a big part of Rubio’s pitch. As a selling point, Rubio’s youth is strongest when used to strike a contrast with Hillary Clinton, the likely Democratic nominee, but it’s an asset he’ll also have to lean on next month in New Hampshire, where he is vying to be the establishment choice with Jeb Bush, John Kasich, and Chris Christie, all older governors who tout their long experience in politics.

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On Friday, Noem and Gardner will hold two events in Rubio’s absence — one for campaign volunteers, and the other at the Iowa Bull Moose Club, a group of Republicans under the age of 40. On Saturday, they’ll barnstorm the state with Rubio. The two are contrast in styles — and after the debate, they settle into a sort of “good cop, bad cop” routine.

Gardner is sunny and smiling, answering every question — even those about other candidates — with effusive praise for Rubio. He won’t take the bait when asked why Cruz has not been endorsed by any of his colleagues in the Senate, and walks back even the most undirected of slights. “You could really see it tonight: the people who were serious — they’re all serious, I didn’t mean to say that wrong, but who have a serious plan, and the seriousness to back it up. And it’s clearly Marco Rubio,” he tells reporters after the debate, with a smile on his face.

Noem, on the other hand, readily goes on the attack.

#related#“From what I’ve heard come from Donald Trump, from what I’ve seen of actions coming out of Ted Cruz, they’re not the right people for the job,” she tells reporters after the debate. “Ted Cruz says whatever’s popular that day. He votes one way, and then a month later will vote another way. He’ll take a position, write an op-ed on something as critical as our economic future and trade with foreign countries, and then he’ll change his mind because the political winds are blowing another direction. I don’t want another president like that.”

Asked if this will be their only visit to the state, Gardner, who many Republicans believe harbors presidential ambitions of his own — “my wife would say, uh, she’d throw me out of the house,” he jokes when the topic is raised — heartily promises to return if the Rubio camp wants him.

Noem, however, is more circumspect.

“Depends on if we help or hurt!” she laughs.

— Alexis Levinson is the senior political reporter for National Review.