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Singer/songwriter Don McLean still closes out every concert with his 1972 song American Pie. Now, McLean is gaining an entire new generation of fans as a documentary examining his life hits stores September 11.

"I was trying to come up with something that would capture America in a certain way," McLean, 66, told us in a recent interview.

Today, the song is revered as a classic, but the crooner revealed that the initial response was tepid: "The audience went: {Yawn}, that was long," McLean said. The song is clocked at 8 minutes and 36 seconds.

It was a polar opposite response last summer at Glastonbury as legions of young people sang along.

Part of the song's longevity is owed in part to Madonna who did a cover of the tune in 2000.

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"People say, 'Do you like Madonna's version?' And I say, 'Yeah, millions of kids got turned on to it, so she did me a wonderful solid for doing that," said McLean.

Don McLean: American Troubadour is available tomorrow.