Despite deferring the draft to serve in the Vietnam War, Republican presidential front-runner Donald Trump boasted of a military-like training that he said was better than that held by many entering the service.

Trump claimed the expensive, military-themed preparatory school he attended gave him more training than experienced by a lot of the individuals who go into the armed services, according to an advance copy of an upcoming biography “Never Enough: Donald Trump and the Pursuit of Success" obtained by msnbc.

"I felt like I was in the military in a true sense," Trump said of his studies at New York Military Academy, "because I dealt with the people."

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He also felt as if he had experience the "military life," author Michael D'Antonio wrote in the book, which will be released on Sept. 22 amid Trump's presidential bid. The candidate currently leads the Republican field with strong double digits in both early primary states of Iowa and New Hampshire, according to a new NBC/Marist poll released on Sunday.

The comments are likely to rankle some, particularly since Trump has mocked and derided Sen. John McCain for being captured and held as a prisoner during the Vietnam War. Trump deferred the draft at the time because of bone spurs, something he routinely downplays and evades questions on now.

The biography tracks Trump’s ambitions, temperament, and life from childhood to his presidential bid and, according to The New York Times report, Trump is blunt in his analysis of himself.

“When I look at myself in the first grade and I look at myself now, I’m basically the same. The temperament is not that different,” Trump says in the book.