Does Donald Trump have a God problem?

Can Republican presidential hopeful Donald Trump position himself as the candidate of the evangelical right?

It would seem to be a bit of a challenge.

The New York billionaire said he doesn't know if he's ever asked God for forgiveness and referred to a communion wafer as "my little cracker" during a religious-affiliated presidential forum in Iowa. He won't cite a favourite Bible verse. He's been married three times. He was once avowedly pro-choice on abortion. And when an interviewer recently asked him about God, he spent more time talking about an oceanfront real-estate deal.

It's a far cry from the more detailed profession of faith made by competing candidates like retired neurosurgeon Ben Carson, former Arkansas Governor (and Southern Baptist minister) Mike Huckabee and Texas Senator Ted Cruz.

Even former Florida Governor Jeb Bush - a no-show at Friday's event - speaks openly of his adult conversion to Roman Catholicism.

And yet there was Donald Trump, childhood Bible in hand, making a play for the support of right-wing religious activists at the Family Research Council's Values Voter Summit in Washington DC on Friday.

"I brought my Bible," he said, noting it was from the First Presbyterian Church in New York City and pointing to an inscription on the inside cover. "This was written by my mother, with my name, with my address, with everything."

It took him a while to get back to religion in his speech - he first felt obliged to take swipes at departing House Speaker John Boehner (for which he was cheered) and fellow candidate Marco Rubio (for which he was booed), but he eventually tried to speak his audience's language.

"I believe in God," he told the crowd of over a thousand. "I believe in the Bible. I'm a Christian."

He followed it up by taking a firm stand in favour of Christmas.

"I love Christmas. You go to stores now, you don't see the word 'Christmas'," he said. "Remember the expression 'Merry Christmas'? You don't see it anymore. You're going to see it if I get elected, I can tell you right now."

And that was mostly it - the sum total of his appeal to his audience's evangelism in his nearly 30 minute address.

Donald Trump offers a closer look at his childhood Bible

Many in the crowd weren't buying it.

"Only God knows his true relationship with God, but as the Bible says, 'you will know them by their fruit'," says Pam Orebaugh of Liberty Lake, Washington. "He's not a bad person, but he's definitely not one championing and being very verbal about being a Christian, religious freedom, being pro-life."

"Where was he 10 years ago?" she asks.

Damon Boyle of Eldersburg, Maryland, calls Mr Trump "very entertaining", but it would take more than that to win his support.

"He's an excellent businessman. He's an excellent executive," he says. "But in terms of a Christian, what has the man done?"

These sentiments were backed up by a straw poll of Values Voter Summit attendees released on Saturday, which put Mr Trump in fifth place with 5% - well behind Mr Cruz, who garnered 35%.

Mr Trump likes to boast that national opinion polls show him with strong backing from religious voters. A recent Fox News Survey had the New Yorker in first place among white evangelicals with 29%.

Donald Trump is competing for evangelical support with Values Voter Summit straw-poll winner Ted Cruz and others

A Gallup poll from mid-September, however, found evidence of weakness in Mr Trump's support. He had a net favourability rating of 22% among "highly religious" voters, putting him 12th- well behind Mr Carson (56%), Mr Huckabee (49%) and Mr Rubio (49%).

"No sign here of any special appeal on the part of Trump to highly religious Republicans," writes Gallup's Frank Newport.

So does Donald Trump have a God problem?

White evangelicals made up 57% of the electorate in Republican Iowa Caucuses in 2012 and were essential to the former Senator Rick Santorum's surprise victory there. They're also a key voting bloc in the eight Southern states that are joining together to hold their primaries on 1 March 2016.

For a while, it appeared that Mr Trump was going to give the Values Voter Summit a pass, prompting Family Research Council President Tony Perkins to question his commitment to religious voters.

"I think that is going to send a message to evangelicals and values voters that he wants their support, but he is not really interested in having a conversation with them," Mr Perkins told the Christian Post.

When Mr Trump changed his plans, Mr Perkins changed his tune.

"It is part of beginning a conversation if he wants to build a relationship with evangelicals," Mr Perkins said in a Washington Times interview, adding that a fifth-place showing in the straw poll "is actually pretty good".

Mr Trump may not be a natural fit for this Republican constituency, but it appears he's not going to cede these voters to another candidate without a fight.

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