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It's time for the Republican establishment to accept the fact that Donald Trump is not only a viable presidential candidate, but his lead is real, his candidacy is real and his support is real, Frank Luntz said on "Hannity" tonight.

Luntz explained that a recent focus group's support for Trump went up, whether he showed them positive or negative information on the GOP front-runner.

"I've never seen anything like it," Luntz said, explaining that many voters applaud Trump's "spicy" language.

He added that establishment Republicans waited too long to challenge Trump, so they've lost credibility with his supporters.

"Now they are seen by Trump voters as part of the problem, not part of the solution. So when they attack, it actually builds Trump's support."

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