As Mitt Romney scours the South for endorsements from evangelical leaders, he is getting some unusual advice on how to explain his Mormon faith: Don't try to be one of us.

"I told him, you cannot equate Mormonism with Christianity; you cannot say, 'I am a Christian just like you,"' said Rep. Bob Inglis of South Carolina, which is scheduled to hold the first primary among the Southern states. "If he does that, every Baptist preacher in the South is going to have to go to the pulpit on Sunday and explain the differences."

This advice, which reflects the views of many Southern Baptists and other evangelicals, makes Romney's co-religionists bristle. "The fact that we are Christians is non-negotiable," said Kim Farah, a spokeswoman for The Church of Jesus Christ of Latter-day Saints.

In seeking the Republican nomination, Romney, 60, has to court the churchgoing voters who make up almost 30 percent of the party's electorate. Evangelical leaders are urging him to explain his faith, much as John F. Kennedy addressed his Catholicism during his 1960 presidential run. In ways, Romney faces a tougher task than Kennedy did.

Evangelical leaders say Romney, unlike Kennedy, won't be able to defuse the religion question by citing the First Amendment of the Constitution and advocating a rigid separation of church and state. Many Christian conservatives blame such a separation for a variety of social ills.

"We need more injection of an understanding of God in our political life," said Roy Moore, the former chief justice of the Alabama Supreme Court and a potential third-party, anti-abortion presidential candidate. "I am looking for a candidate that understands that this nation is established on a particular God."

Romney, who says he accepts Mormon doctrine "true blue, through and through," must also contend with the way his religion is negatively depicted, from HBO's hit comedy "Big Love," whose supposedly Mormon protagonist juggles three wives, to polygamy trials in Utah.

Married to the same woman for 38 years and a grandfather of 10, Romney presents himself as a model of Christian family values. Still, evangelicals say they remain skeptical for two reasons: a faith they consider a cult and a record as governor of Massachusetts that includes support for abortion and gay rights.

Republican strategists argue that time is wasting for a Kennedyesque speech to explain the role religion will play in a Romney White House. Such an opportunity, they say, may have been squandered when he avoided the subject at a gathering of evangelical voters in Washington this month.