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Story highlights

"This is a very unusual year. No one is unbeatable. This election is not going to be decided by one or two states," Rubio said

Rubio's comments come one day before Iowans head to the polls in the critical first-in-the-nation voting state

Washington CNN —  

Marco Rubio, trailing both Donald Trump and Ted Cruz in Iowa polling, charged Sunday that neither of his rivals is “unbeatable” ahead of Monday’s Iowa caucuses.

While he disparaged Trump’s campaign as “the greatest show on Earth,” he saved his most pointed criticism for Cruz.

“This whole notion Ted has that he’s the only conservative, I think as people learn more about his record, they’ll realize what he really is very calculating,” Rubio told CNN’s Jake Tapper in an interview that aired Sunday on “State of the Union.”

“He’s always looking to take whatever position it takes to win votes or raise money, and we’re not going to beat Hillary Clinton with someone that will say or do anything to get elected,” Rubio said.

He charged the Texan with regularly misrepresenting his immigration positions, particularly on the subject of whether he supports “amnesty,” or allowing undocumented immigrants to stay in the U.S.

“I’ve tried to fix a problem that’s a very serious issue in Texas and in Florida, and it’s a hard issue,” Rubio said. “And clearly we’re not going to be able to do it comprehensively and we’re not going to be able to do it until we first enforce our immigration laws. But I don’t support amnesty. We’re not going to have amnesty when I’m president. There’s going to be real consequences for violating our law.”

Asked by Tapper if Trump could be stopped, Rubio said, “Sure.”