One of the most heated moments during Saturday's GOP debate occurred when New Jersey Gov. Chris Christie called out Sen. Marco Rubio (Fla.) for giving a "memorized, 25-second response" -- an argument Rubio went on to inadvertently support.

While responding to Christie's attacks, Rubio gave the same answer three times, repeating, "Obama knows what he's doing."

"There it is," Christie said after Rubio made the remark for the third time.

Rubio repeated the comment again later in the debate and was booed.

Watch a clip of the moment above.

Amber Ferguson contributed to this report.

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