NEW YORK — (CNN) There are few things Donald Trump is more particular about than his hair.

And on Thursday, Jimmy Fallon asked if he could mess it up.

First, Trump winced and grimaced, shaking his head as the “Tonight Show” audience erupted in a smattering of applause and cheers.

Moments later, the Republican nominee relented.

“The answer is yes, but the people in New Hampshire, where I’m going to be in about an hour from now, I hope they’re going to understand,” Trump said. “Go ahead.”

Trump’s signature coif has long been the subject of intense scrutiny, including from those who’ve questioned whether Trump’s do is the real thing.

To test those claims, Trump has allowed interviewers and even random attendees at a couple of campaign events to touch his hair, but never mess it up — until now.

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