Many Mormons here are rooting for Mr. 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, Mr. Romney, former governor of Massachusetts, recently was the leader in campaign fund-raising; his candidacy is, for many Mormons, a historic moment of arrival.

But even for the many Mormons who support Mr. Romney, the moment is fraught with anxiety because his candidacy is bringing intense scrutiny to their church, and could exacerbate longstanding bigotry.