SPARTANBURG, S.C.  -- Republican Mike Huckabee spoke from the pulpit Sunday, not as a politician but as the preacher he used to be, delivering a sermon on how merely being good isn't enough to get into heaven.

Huckabee is vying for support from the Christian conservatives who dominate the GOP in South Carolina, which on Saturday chooses a Republican presidential nominee. A former Baptist minister and Arkansas governor, Huckabee is competing for their votes with fellow southerner Fred Thompson.

As in Iowa, where Huckabee won the Jan. 3 caucuses, Huckabee is rousing pastors to marshal their flocks for him. He pitches himself as someone who not only shares their views against abortion and gay marriage but who actually comes from their ranks.

On Sunday, Huckabee avoided politics entirely, instead preaching about humility and trusting in Jesus to open the gates of heaven.

"The criteria to get into heaven is you have to be not good, but perfect. That's the real challenge in it," he said at First Baptist North Spartanburg, a megachurch with 2,500 members.

"On that day, when I pull up, I'll be asked, `Do you have what it takes to get in?"' Huckabee said. "And if I ask, `Well, what does it take to get in?' 'Gotta be perfect."'

"Well, I'm afraid I don't have that, but you know what, I won't be there alone that day. Somebody is going to be with me. His name is Jesus, and he's promised that he would never leave me or forsake me," he said.

Huckabee didn't ask for votes or discuss the campaign, but senior pastor Michael S. Hamlet encouraged the congregation to vote according to how they try to live their lives, by the principles of Bible scripture.

"I'm going to tell you something, when you go vote, you ought to follow those principles," Hamlet said.

Huckabee defended his campaign's reliance on pastors to spread the word about him to their congregants.

"They can't mobilize for example, from the pulpit, get up and say to everybody, 'the bus leaves the church at 8 a.m. on Saturday.' It's a matter of urging them to use the influence they have to get their people out to vote, and I hope they will. Why wouldn't they?" Huckabee said at an afternoon news conference before a flight to Michigan.

Huckabee also is hoping for a majority of the Christian conservative vote in Michigan, which votes Tuesday. He emphasized his opposition to abortion during a meeting with about 100 pastors in Grand Rapids on Saturday, urging them to use their address books and e-mail lists to mobilize others.

Polls there have shown him running in third place, behind former Massachusetts Gov. Mitt Romney and Arizona Sen. John McCain, winner of the New Hampshire primary last week.

In contrast to Huckabee, Thompson held no public events Sunday in South Carolina, where Huckabee has the edge following his Iowa caucus win.