The irony, in Obama's case, is that despite his orthodox utterances -- there's "something about the resurrection of our savior, Jesus Christ, that puts everything else in perspective," he said at this year's Easter breakfast -- polls continue to show widespread confusion about his faith.

Only half the country can correctly identify Obama as Christian, according to one recent Pew poll, while 17% falsely believe he is a Muslim.

"He's a Christian and he professes his Christian faith -- I don't know what else this man has to do to get that into folks' ears," says Caldwell, who was also close to George W. Bush.

But Obama's public piety has helped him bond with young evangelical leaders, who are less tied to the GOP than their parents' generation.

"I was struck by the specificity of what he described in terms of theology and what it means to him," says Gabe Lyons, one such leader, describing a White House Easter breakfast he attended. "His message is very specific and very orthodox."

Where exactly that new orthodoxy comes from -- the pressures of the White House, a new circle of religious advisers or, to a certain degree, from political calculation -- may become clearer after Obama's presidency, if he opens up about such matters.

Until then, the president is likely to keep speaking "Christianese" -- and resisting Christian labels.