"I do believe we're entitled to ask what a prospective president believes," Keller said, noting he has found pieces about Mitt Romney's time as a Mormon leader illuminating.
"I think that's not only an OK line of reporting, I think that's something we should do bigger and should be a routine thing."
As religion writers descended on the nation's capital for their annual conference, several of the topics focused on the nexus between religion and the presidential race: What boundaries should journalists have? How has religion impacted the race? Is religious freedom a conversation driver?
As expected, the Mormon faith was frequently mentioned as Romney is the first member of his religion on a major-party presidential ticket.
Despite a big speech on Mormonism in his 2008 White House run, Romney didn't speak about his faith much until using it during the Republican National Convention to highlight his character and boost his likeability.
President Barack Obama, too, has been largely silent on his personal faith.
"It's been pretty quiet and almost absent in the general election," said Amy Sullivan, a contributor to Time magazine and The Atlantic. "That's how it should be."
Sullivan and Keller differed on how far reporters should go in covering aspects of a candidate's faith, with Keller arguing that it's up to the candidate to answer or not.
"I don't worry too much about whether a question is legitimate to ask," Keller said, noting that one-time presidential contender Bill Bradley refused to talk about his personal faith.
"We cannot cede to the candidates the questions that we can ask."
There's a worry, though, Sullivan responded, that there should a logical reason for asking the question beyond just trying to grab headlines.
"The question needs to meet this basic test to be relevant to telling us how a candidate would govern," she said.
On that point, Valerie Cooper, an associate professor of religious studies at the University of Virginia, wondered why there hasn't been more mainstream press coverage of The Church of Jesus Christ of Latter-day Saints' beliefs with regard to blacks.
Cooper, who is black, cited Mormon scripture to argue that there are lingering questions about what LDS faithful believe about those with black skin.
"How do you know until you ask what you'll learn from a candidate about his or her faith," she said. "They're adults, they can handle it. After all they've been asked things like 'boxers or briefs?' "