The poll, which has a margin of error of plus or minus 3 to 4 percentage points, shows 57 percent of Utahns see themselves "very religious," compared with 59 percent of Mississippians.
In fact, Utah is the only Western state in the top 10; most are in the Deep South.
The poll defines that category as people who attend worship services at least weekly and make religion a part of their daily lives.
Despite Utah's large number of "very religious" residents, a significant segment (28 percent) say they are "nonreligious," while 15 percent are "moderately religious."
Pam Perlich, senior research economist with the University of Utah's Bureau of Economic Research, said the numbers reflect the dominance of The Church of Jesus Christ of Latter-day Saints in Utah.
"As Vatican City is the center of the Catholic Church," Perlich said, "the [Mormon] temple in downtown Salt Lake City is the religious center for Mormons" and the "bull's-eye" of an LDS cultural zone in the West.
LDS Church figures show 62 percent of Utahns are Mormons, although those numbers do not reflect the members' level of activity in the faith.
Still, those numbers shape Utah culture and some of its conflicts.
"It's a highly hot-button issue in every setting," said the Rev. France Davis, longtime pastor of Salt Lake City's Calvary Baptist Church. "Not only do they [Mormons] have influence at the religious level, but economically and politically."
Davis points to the LDS Church's recently completed City Creek Center as an example of that economic clout. The church launched the $2 billion project to revitalize downtown and protect its sacred campus, including Temple Square, from urban blight.
Davis views Utah, with its many churchgoing residents in a variety of faiths, as a "religion-friendly" place.
Stephen Goldsmith, associate professor of city and metropolitan planning at the University of Utah and Salt Lake City's former planning boss, said Mormon influence shows up in the way cities are laid out he points to the grid system of wide streets and how they are governed.
"It's very complex," Goldsmith said. "When a religion has rules that it expects people to adhere to, it can affect how people make rules."
When Salt Lake City was asked to permit outdoor dining at restaurants, Goldsmith recalled, it had to require a 3-foot-high fence around sidewalk eateries to deter people from passing alcoholic beverages to others a concession to LDS strictures against drinking.
Lane and others say the LDS influence is obvious in the Legislature.
In a recent survey conducted by The Salt Lake Tribune, legislators said their personal religious views have more influence on their votes than direct statements from LDS Church headquarters. More than three-quarters (77 percent) of legislators responding indicated they were Mormon.
Lane said the gulf between religious and nonreligious people in Utah underscores the need for the constitutional separation of church and state.
Civil rights attorney Brian Barnard said Utahns, especially those in power, would do well to remember how their Mormon forebears were treated in Missouri and Illinois when they were a religious minority.
He said that past should be "a substantial reason for the people of Utah to be concerned about the separation of church and state, and how to keep government out of religion, and religion out of government."
Most religious states
Mississippi • 59 percent
Utah • 57 percent
Alabama • 56 percent
Louisiana • 54 percent
Arkansas • 54 percent
South Carolina • 54 percent
Tennessee • 52 percent
North Carolina • 50 percent
Georgia • 48 percent
Oklahoma • 48 percent
Source: Gallup "State of the States" poll