DALLAS - Religion is not proving to be a clear-cut factor in the 2008 U.S. White House race, taking a back seat to the Iraq war and domestic issues, but most Americans still feel faith is an important attribute in their president, according to a survey released on Thursday.

The Pew Forum survey also found that U.S. presidential candidates need not be seen as very religious to gain wide voter acceptance, noting that the Democratic and Republican front-runners -- Hillary Clinton and Rudy Giuliani -- are viewed as the least religious among the top contenders.

The survey's findings are sure to be scrutinized by both parties as they vie for the vote of the faithful in the United States, where rates of churchgoing and strong religious conviction are far higher than elsewhere in the developed world.

"Religion does constitute a bar that candidates must successfully clear but the poll suggests it is not very high. ... And all the leading candidates seem to be clearing this bar," said Gregory Smith, a research fellow at the Pew Forum on Religion and Public Life.

The poll, conducted nationwide among 3,002 adults from Aug. 1 to 18, found that the Iraq war and domestic issues such as the economy top the list of voter priorities.

"Hot-button" social issues such as abortion and gay marriage are way down the list -- except among white evangelical Protestants, 56 percent of whom said they were very important concerns in their presidential voting decisions.

White evangelical Protestants are a key base of support for the Republican Party, which has used issues like abortion in the past to get this constituency to the ballot box.

But even among this core group, domestic concerns such as the economy and the situation Iraq were more important.

Among the top tier of Republican candidates, the pro-choice (on abortion) and pro-gay rights Giuliani was only regarded as "very" religious by 14 percent of those who offered an opinion on this point -- a smaller percentage than the other leaders.

Yet the former New York mayor leads the Republican field and the poll indicates that 63 percent of Americans see him as at least "somewhat religious."

Former Massachusetts Gov. Mitt Romney was regarded as very religious by 46 percent of the respondents who offered a view on this but the political capital gained was diminished by concerns about his Mormon faith.

"A quarter of Americans -- Democrat, independent and Republican alike -- say they would be less likely to vote for a presidential candidate who is Mormon, and these people have substantially less favorable impressions of (Romney)," the Pew Research Center said.

Among the survey's other key findings:

- About 69 percent of Americans agree that it is important for a president to have strong religious beliefs.

- Hillary Clinton is only regarded as very religious by 16 percent of Americans versus 24 percent for Barack Obama and 28 percent for John Edwards. But majorities see all three top Democratic contenders as being "somewhat" religious.

- Public awareness of Giuliani's stance on abortion is not widespread. Overall, just 22 percent of the public and 31 percent of Republicans know Giuliani supports abortion rights.

- Domestic issues at 78 percent and the Iraq war at 72 percent are the main voter priorities, topping social issues, which were viewed as very important by 38 percent.