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Mark Steyn reacted to the fifth GOP debate on "Hannity" tonight, saying that Jeb Bush attacking Donald Trump was a case of too little, too late.

Steyn said the problem is that Bush has burned through a significant portion of his campaign's $100 million war chest, yet he's at three percent in the polls, while Trump's at 41 percent.

"Basically, Jeb Bush is Jim Gilmore with $100 million," Steyn stated. "That’s what Trump has done to him, so he left it too late to push back, I think."

Steyn added that Trump, as an "insurgent candidate," has shaken up the entire GOP field and brought issues like immigration to the forefront.

"The establishment has lost control of this thing."

Get more GOP debate reaction from Steyn in the clip above.

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