The Democratic National Committee's chief financial officer apologized Saturday for the "insensitive" comments in an email made public by WikiLeaks.
In a Facebook post, Bradley Marshall said,"I deeply regret that my insensitive, emotional emails would cause embarrassment to the DNC, the Chairwoman, and all of the staffers who worked hard to make the primary a fair and open process. The comments expressed do not reflect my beliefs nor do they reflect the beliefs of the DNC and its employees. I apologize to those I offended."
Marshall's email was one of more than 19,000 emails from Democratic Party officialspostedFriday to WikiLeaks.
In a May 5 email toDNC press secretary Mark Paustenbach, communications director Luis Miranda and CEO Amy Dacey, Marshall appears to write about a plan that would question Sanders' religion.
"It might make no difference, but for KY and WVA can we get someone to ask his belief. Does he believe in a God. He had skated on saying he has a Jewish heritage. I think I read he is an atheist. This could make several points difference with my peeps. My Southern Baptist peeps would draw a big difference between a Jew and an atheist," Marshall wrote in the email.
Though the email does not specifically name the Vermont senator, it mentions a man of "Jewish heritage," and makes reference to voters in Kentucky and West Virginia, two states that were holding primary elections later that month.
In an interview with The Intercept after the leak, Marshall said “I do not recall this. I can say it would not have been Sanders. It would probably be about a surrogate.”
Sanders was the only Jewish candidate from either party.
On Saturday, presumptive nominee Hillary Clinton's campaign released a statement that said: "We are very proud of the campaign that we ran. Hillary Clinton has said a number of times publicly that Sen. Sanders ran an extraordinary, hard-fought campaign based on a real vigorous, and contested primary.
"This is further evidence the Russian government is trying to influence the outcome of the election," the Clinton campaign statement said, referencing a hack by Russian government cyber operations into the DNC's computer network.
Sanders' campaign manager Jeff Weaver said his team was "disappointed" by the leaked DNC emails.
"Someone does have to be held accountable," Weaver said in an interview with ABC News on Saturday. "We spent 48 hours of public attention worrying about who in the [Donald] Trump campaign was going to be held responsible for the fact that some lines of Mrs. Obama's speech were taken by Mrs. Trump. Someone in the DNC needs to be held at least as accountable as the Trump campaign."