By Jon Keller

BOSTON (CBS) — Donald Trump may be leading his Republican rivals in the polls, but former New Hampshire Gov. John Sununu believes the Trump boomlet will be short-lived.

“It will collapse, and it will probably collapse, to borrow a line, not with a bang, but with a whimper,” Sununu told WBZ political analyst Jon Keller.

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Sununu said voters are responding positively to Trump’s words, but once they look at the man behind his statements, “that’s where it falls apart.”

“They’ll see a guy who’s a great showman, they’ll see a guy who puts out bumper sticker slogans,” Sununu said. “But when you ask him to go beyond the bumper sticker with substance, it falls apart.”

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Sununu was White House chief of staff to former President George H.W. Bush, and has written a new book called “The Quiet Man: The Indispensable Presidency Of George H.W. Bush.”

He told Keller that Bush hasn’t received the recognition he deserves, and also talked about what the new generation of leaders is missing.

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You can listen to Keller At Large on WBZ News Radio every weekday at 7:55 a.m. You can also watch Jon on WBZ-TV News.

Jon Keller