WASHINGTON — When it’s time to relax, some senators play golf. Others pour themselves a drink.

But Sen. Bob Bennett, R-Utah, isn’t inclined toward the greens and his faith preaches against alcohol.

Instead, he’s spent time on and off for the last seven years building a defense of the Book of Mormon, one of the key tomes of the Church of Jesus Christ of Latter-day Saints. The three-term senator whose job puts him at the center of political power has now delved into a different debate: whether the book Mormons believe was revealed by an angel to their founder Joseph Smith in the 1820s is authentic.

“I live in a world where sometimes you have to respond to conflicting opinions,” said Bennett in an interview. A former missionary and bishop and the grandson of a past president of the church, the senator turns 76 this month (Sept.).

Bennett says “Leap of Faith: Confronting the Origins of the Book of Mormon,” was sparked by the “shallow treatment of a serious subject” by media who covered the church and its scripture around the 2002 Winter Olympics in Salt Lake City.

Scholars outside the Mormon faith also have strong doubts about the Book of Mormon’s historical accuracy because they find scant evidence of the large groups of people it says roamed the earth centuries ago.

“Thus, for anyone truly interested in the Church and its claims, a thorough examination of the Book of Mormon as a possible forgery is a requirement,” Bennett wrote.

In his book, published this month (September) by the Mormon publisher Deseret Book, the senator delves into the complex stories and basic doctrines of the Book of Mormon. In a conversational tone, he recounts and analyzes its stories of the migration of the groups and the appearance of Christ before them.

Beyond his family history and personal interest in the faith, Bennett cites another reason for his ability to delve into the debate. As an executive for two companies owned by billionaire Howard Hughes, Bennett worked to prove that an autobiography of his boss was a forgery.

“I was the one who talked to the newspapers and talked to the press and had the Life magazine reporter in my office, trying to convince him this whole autobiography was nonsense,” recalled Bennett, who was the public relations director for Hughes’ Summa Corporation.

Now, the senator is arguing that the Book of Mormon is not a forgery, saying its intricacy and door-stopping verbosity — 584 pages in its original edition — help prove it is real.

Beyond the “spiritual tug” believers feel when they read it, he said, “The greatest single evidence of the Book of Mormon is its length and its complexity.”

But Bennett acknowledges the arguments of skeptics who simply can’t get past the supernatural role of the angel Moroni, who Mormons believe revealed buried gold plates to Smith so he could translate the histories detailed on them.

Neither does he shy away from the argument that there is little solid evidence of the people the book describes.

“If you have a civilization that has populations in the millions, that civilization ought to leave behind an archaeological footprint that somebody could find,” said Bennett.

“There are Mormon archaeologists who say we have found sites but they’ve been unable to convince any of their colleagues that are not of the Mormon faith.”

Bennett acknowledged he had trouble finding a non-Mormon publisher to release his research. He said several were initially interested when he sought a publisher during the presidential campaign, but that interest waned when Mormon candidate Mitt Romney dropped out of the race.

“The Book of Mormon has never been examined seriously by scholars outside the faith,” said Terryl Givens, a Mormon and independent scholar at the University of Richmond whose “The Book of Mormon: A Very Short Introduction” was published in August by Oxford University Press.

“The story of its coming forth is too fantastical for non-Mormons to overcome.”

Jan Shipps, a non-Mormon scholar who has studied Latter-day Saints for half a century, said she hasn’t assessed the veracity of the Book of Mormon but said it certainly has its critics.

“They say it was either a copy of something or that it was a forgery of some kind, that a man without any kind of education could not have written this book,” said Shipps, former professor at Indiana University-Purdue University Indianapolis.

The senator made a point of separating his work from both church and state.

Bennett left his senatorial title off the book cover and he noted inside: “This is entirely my own work, neither commissioned nor sanctioned by the Church.”

Church spokeswoman Kim Farah said church officials don’t comment on books about Latter-day Saints topics — by Mormons or non-Mormons “except to say that such publications represent the personal opinions and expressions of the respective authors.”

Bennett said some church members have expressed qualms about his work but he considers his approach to be an honest one.

“I’ve had some members of the church say to me, `We like the fact that you’re being evenhanded here, but we’re really disturbed that you’re raising some problems,”‘ he said. “I came to realize that you need a leap of faith if you’re going to believe it. You also need a leap of faith if you’re going to reject it.”