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Cruz, Rubio & Kasich Say They Will Support Trump If He Wins Nomination

What did Michigan voters think about tonight's GOP debate in Detroit?

Frank Luntz shared the reactions of his focus group on a special post-debate edition of The Kelly File.

The voters had some very negative things to say about the tone of the debate, objecting to the intense personal attacks and lamenting a lack of substance.

Using words like "sophomoric," "shameful" and "despicable," the voters agreed that this debate did not help the GOP overall. 

Asked who they thought won the debate, the voters overwhelmingly agreed on John Kasich. 

He was praised as the "only adult in the room" and appearing to be more "mature" than the others. 

The low point of the night, according to the voters, was a moment when Rubio slammed Trump University, prompting Trump to argue that the senator "couldn't get elected dog catcher" in Florida.

"We've never tested something so low," said Luntz, adding that Kasich also scored very high during remarks on foreign policy. 

Watch their thoughts above.

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