(CNN) -- The two Democratic presidential candidates frequently weave religion into their stump speeches, but Sen. John McCain, the presumptive Republican nominee, has been more tight-lipped on the subject.
Sen. John McCain doesn't make his faith a focus on the campaign trail.
Sens. Hillary Clinton and Barack Obama both got personal Sunday night, putting politics aside to discuss their faith at Faith in Public Life's Compassion Forum at Messiah College, about 12 miles outside the Pennsylvania capital of Harrisburg.
McCain declined an invitation to the forum.
For years, the evangelical community has largely supported Republican presidential candidates.
However this year, evangelical leaders have split over McCain, who is struggling to mend fences with some evangelical luminaries like James Dobson, who have expressed disappointment with his selection.
Republican candidates rely on support from the evangelical base, but some are hesitant to embrace McCain.
"Honestly, I haven't gotten a good feel for him. I've been to his Web site a few times and I haven't gotten a good feeling about where he stands when it comes to other issues that aren't mainstream issues that Christians look at," said Doug Enders, an evangelical voter at New Covenant Fellowship Church in Mechanicsburg, Pennsylvania.
McCain was raised an Episcopalian and now belongs to a Baptist church. On the rare occasion he mentions his faith, it is usually within his comfort zone -- the military and its men.
"In the immediacy, chaos, destruction and shock of war, soldiers are bound by duty and military discipline to endure and overcome. Their duty and loyalty belong to their country. They find solace in their faith in God. But their strongest loyalty, the bond that cannot break, is to the cause that is theirs alone -- each other," he said earlier this month in Jacksonville, Florida.
McCain, 71, is from an older generation, one that is more private about prayer.
"I'm unashamed and unembarrassed about my deep faith in God. But I do not obviously try to impose my views on others," he said Friday.
But he's equally quiet about his policy positions important to evangelicals, like his opposition to abortion, and has angered social conservatives on a host of issues, such as support for embryonic stem cell research.
He's caused further rifts with conservatives by opposing President Bush's signature tax cuts, co-sponsoring the campaign finance reform law that now bears his name and supporting a controversial White House-backed plan to offer a path to citizenship for illegal immigrants.
"He has some problems, no question about it, and if he talks about those things that are important and has a track record behind it, I think he can win people over," said Mike Geer, with the Pennsylvania Family Institute.
Brett Hartman, pastor of the New Covenant Fellowship Church, said he disagrees with McCain on several issues, but he's not bothered that McCain doesn't talk much about faith.
"Sometimes when people kind of use the platform of their faith ... it takes away a little bit from their integrity," he said.
He tells his conservative flock to do what the Gospel teaches and judge a candidate by his actions, not words. E-mail to a friend