When asked about a candidate's belief in a divine being, 84 percent of GOP respondents rated it as very important, compared with 55 percent of Democrats and 58 percent of independents.
"Clearly, religion is much more important to Republicans," said Brad Coker, of Washington, D.C.-based Mason-Dixon Polling & Research, which conducted the Dec. 12-16 survey for The Tribune.
Important, too, is a candidate's particular faith, though not nearly as much.
The national poll, with an overall margin of error of plus or minus 3.1 percentage points, found 43 percent of likely voters labeled it important for a candidate to belong to a certain religion, compared with 56 percent who said it wasn't.
But most Republicans (52 percent) view a candidate's particular faith as "very" or "somewhat" important.
More telling may be that while 67 percent of Americans and 67 percent of Democrats want their White House contenders to be Christians, that number jumps up to 87 percent for Republicans. At the same time, 22 percent of Democrats, compared with the GOP's 8 percent, said it was "not important."
The partisan split is likely attributed to the larger number of secular Democrats, said Michael Cromartie, vice president of the Ethics and Public Policy Center, which studies public policy through a Christian viewpoint. He said while most Democrats are people of faith, the party "just has a lot more nonbelievers in it."
Independents, who by definition tend to be less dogmatic about their politics, apparently are less rigid on issues of faith as well. Only 45 percent said they wanted their presidential candidates to be Christians, while 48 percent said it wasn't important at all.
The strong response from partisans didn't surprise Coker, who said history shows that this isn't a new trend.
"If you look at it, every president we have ever had has been Christian," Coker said. "Some might not have been particularly religious, but on paper they have said they are some kind of Christian."
Although the U.S. Constitution clearly bars a religious test for political candidates, it appears that voters have all but established a de facto litmus test for national office-seekers one that major candidates have confronted in recent years.
Pesident Barack Obama has fought to correct erroneous rumors that he is a Muslim, when, in fact, he is a Christian.
Mormon politicians such as Romney and Huntsman, a former Utah governor, have had to deflect accusations from some Baptists and evangelical Protestants who argue that members of the Utah-based Church of Jesus Christ of Latter-day Saints aren't Christians. Others have labeled the worldwide faith a cult.
Most recently GOP candidate Newt Gingrich accepted the resignation of his political director in Iowa over such comments. And the head of South Carolina's Southern Baptist Convention told reporters that Romney's Mormonism would be more cause for concern than Gingrich's past marital infidelity.
While the issue persists, The Tribune poll found that 52 percent of Americans view Mormons as Christians, with 22 percent saying they are not and 26 percent unsure.
More than 60 percent of Republicans, Catholics and people who said they were not religious consider Mormons to be Christians, while 49 percent of Democrats, 46 percent of Protestants and 44 percent of independents did so as well.
The margins of error for these subsets range from plus or minus 5.2 percentage points to 8.3 percentage points.
White evangelicals often are seen as one conservative group most likely to criticize the LDS faith, but the poll found that 50 percent see Mormons as Christians, though 29 percent said they were not, the largest among any of the groups polled by The Tribune.
Some respondents were open with their concerns about Mormons.
Linda Dameron, an evangelical Republican living in Independence, Mo., argued it is essential for candidates to believe in Jesus Christ.
"I have a tendency to believe if a man cannot hear from God, he is not going to know how to direct the country," she said. But Dameron doesn't believe Mormons worship the same Christ as she does. "I do believe they are moral people, but again there is a difference between being moral and being saved."
When asked whom she would support if Romney faced off against Obama, she said, "I don't have the slightest idea."
Grace Harley, an evangelical preacher in the Washington, D.C., area, said she wouldn't hesitate to support Romney over Obama, but she hopes it doesn't come to that.
Harley has strong views on homosexuality and believes the Democratic president has catered too much to gay Americans. So even though she doesn't consider Mormons to be Christians, she said she would support a candidate who holds views similar to her own.
Romney recently acknowledged that he would lose some votes because of his Mormonism, but he downplayed the importance of religion in the 2012 race.
"The great majority of voters would like a person of faith to lead the country," he told The New York Times earlier this month. "I think, however, that most people don't decide who they're going to vote for based on the religion that they happen to be a member of. But there will be some for who that's an issue, and I won't get those votes in some cases. I think that's the minority, particularly in primary states where a lot of people come and vote."
Preview • More poll results coming Friday
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