LOGAN — In this wide valley where the LDS temple dominates the landscape and some neighborhoods boast an LDS chapel every few blocks, Mitt Romney's bid for president is both a proud sign of progress and a cause of trepidation.

Many Mormons here are rooting for Romney, a fellow church member whose success in business, Adonis looks and wholesome family tableau seem to them to present the ideal face of Mormonism to the world. Among the Republican front-runners, Romney, a former governor of Massachusetts, recently was the leader in campaign fund-raising; his candidacy is, for many Mormons, a historic moment of arrival.

"He represents the best of what the church can produce," said Kenneth W. Godfrey, 73, a historian of Mormonism and of this valley about 80 miles north of church headquarters in Salt Lake City.

But even for the many Mormons who support Romney, the moment is fraught with anxiety because of fears that his candidacy will bring intense scrutiny to their church and revive longstanding bigotry.

The Church of Jesus Christ of Latter-day Saints has been fighting for legitimacy since its founding 177 years ago in upstate New York. The church's first prophet, Joseph Smith Jr., was killed by a mob in Illinois, and his followers fled from persecution and settled in Utah.

While LDS Church members are by now successfully integrated and prospering in the American mix, memories of that persecution are still fresh. Many current members can trace their great-great-grandparents to the church's earliest pioneers, and children grow up reading their ancestors' original diaries. Many Mormons fear that Romney's campaign may reopen old wounds.

"I thought we might get mud thrown at us," said Lula DeValve, 82, a retired teacher and a Democrat who volunteers with the League of Women Voters.

John Hatch, 30, a history student at the University of Utah in Salt Lake City, said, "What most Mormons desire is acceptance."

"We see ourselves as normal," Hatch said. "We struggle with those outsiders who see us as weird. ... "

At the core of these tensions is that Mormons consider themselves to be Christians who believe in Jesus Christ and the Bible, but many of their tenets and practices have been denounced by other churches as heretical.

Some Mormons have watched with concern how Romney has responded to grilling by interviewers about his church's distinctive doctrines.

Romney has been questioned about the Mormon definition of God, polygamy, the location of Jesus' arrival when he returns to Earth, and even a mysterious saying attributed to Joseph Smith Jr. called the "White Horse Prophecy," which some interpret as a prediction that when the American Constitution is hanging "by a thread," a Mormon will rescue the nation. (Romney dismissed it, and church leaders in the past have discounted it, saying it is not doctrine.)