DES MOINES, Iowa — Donald Trump wasn't here Thursday night, and it showed. 

Without the billionaire on the stage for the seventh Republican presidential debate, U.S. Sen. Ted Cruz found himself reprising his roles from previous meetings with his rivals: media critic, anti-Washington crusader and target of U.S. Sen. Marco Rubio of Florida. It was a relatively low-key affair compared to some of Cruz's past outings on the debate stage — a fact his campaign acknowledged as it argued the senator nonetheless relayed meaningful contrasts.

"If people tune in for WWE, I mean, they're not getting what they want," Cruz campaign manager Jeff Roe told reporters after the debate. "But if you're a Republican caucus goer, that's, like, good stuff. You got to see a difference in economic policy, in foreign policy, in social priorities."

"Cruz did what Cruz needed to do," added Bob Vander Plaats, an Iowa evangelical leader supporting Cruz.

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Cruz took the most heat from Rubio, a weeks-long sparring partner over immigration and national security issues. Rubio sought to portray Cruz as politically opportunistic, specifically accusing him of trying to "trump Trump" on illegal immigration while not being as tough on the issues as he claims to be. 

"This is the lie that Ted’s campaign is built on — that he’s a conservative guy and everyone else is a RINO," Rubio said. "We’re not going to beat Hillary Clinton with someone who will say or do anything to win an election." 

U.S. Sen. Rand Paul of Kentucky launched a similar offensive against Cruz, calling his Senate colleague the "king of saying, 'You're for amnesty, everybody's for amnesty,' except for Ted Cruz." Cruz, Paul added, has an "authenticity problem." 

Cruz returned the fire with his usual defense of his involvement in immigration reforms efforts in 2013. He insisted his amendments to the so-called "Gang of Eight" bill that Rubio authored were meant to fix problems with it, not offer any form of legalization to people in the country illegally.

After the debate, Cruz and Rubio surrogates traded almost identical talking points from when the immigration issue first flared up between the two candidates at the fifth GOP debate. Rubio spokesman Alex Conant said many Americans know where Rubio stands on immigration, which cannot be said of Cruz. Cruz campaign officials, meanwhile, crowed that their candidate is winning any time immigration is the topic of conservation with Rubio, whose views they see as out of step with much of the Republican base.

As the senators traded barbs inside the Iowa Events Center, Cruz's closest competition was just minutes away at Drake University holding his own event, a fundraiser for veterans. Trump announced Tuesday he would skip the debate, citing problems with the Fox News moderators — particularly Megyn Kelly. 

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Asked about Trump's absence at the start of the debate, Cruz skipped his usual criticism of the billionaire, instead thanking Iowans for welcoming him to their state and offering an upbeat promise. 

“If I am elected president, keep an eye on the tarmac because I will be back," Cruz said, promising to make Iowa "fly-to country," not "flyover country."

Cruz's remarks began a debate that lacked many of the fireworks that characterized his previous debate outing, when he tangled with Trump over questions about his eligibility to be president and the billionaire's stands on social issues. Cruz's surrogates insisted Trump's absence was all downside for the billionaire, whom the senator has challenged to a one-on-one debate Saturday in Sioux City. 

"This is the last interview before people go take a vote, and I think the people of Iowa expected him to be on that stage," Vander Plaats said of the Des Moines debate. "I think the people of Iowa will hold Donald accountable for that." 

Trump's absence effectively made Cruz the frontrunner on the stage, and he seemed reluctant at times to engage too much with his lower-polling foes. Like he has done in a number of prior debates, though, he did find a convenient foil in the debate moderators, criticizing them for trying to get the candidates to attack each other.

"If you guys ask one more mean question, I may have to leave the stage," Cruz joked, reaching for a Trump impression.