A call with all three Democratic campaigns, CBS and members of the Democratic National Committee about how to address the terrorist attacks in Paris quickly turned contentious Saturday over those specific changes.
An aide to Bernie Sanders "threw a fit" when CBS informed the campaigns in a conference call Saturday that the Democratic debate would kick off with a focus on the attacks in Paris, a person who was on the call told CNN.
"Once CBS informed the campaigns the debate was going to kick off with a focus on the attacks in Paris last night, he (Mark Longabaugh, a Sanders strategist) completely lost it. He threw a fit for several minutes," the source said.
But a DNC debate coordinator tells CNN that the argument on the call earlier Saturday was not about whether the debate would focus on Paris, adding that it is unfair to say Sanders' campaign did not want to debate foreign policy.
"No, no," the coordinator said when asked about whether Sanders' aides were worried about debating Paris.
"What happened was that we have had the format of the debate finalized for several weeks," the coordinator said. "CBS wanted to get rid of the opening statements and start with a 30-second answer on Paris," the coordinator said. "It was never a conversation of whether we talk about foreign policy or not. They just wanted a longer opening comment."
But according to the source on the call, Longabaugh argued that "this wasn't part of the deal. It shouldn't be allowed. It wasn't advertised as a foreign policy debate and it's turning into a debate it wasn't supposed to be."
The source also said Longabaugh's outburst was "met with stunned silence. It was really crazy."
CBS stood by its change and representatives for Hillary Clinton and Martin O'Malley's campaigns agreed to the change, the source added.
The incident was first reported
Jeff Weaver, the Vermont senator's campaign manager, backed the account that the dispute was largely over cutting the opening statements from 90 seconds to 30 seconds in order to get right to questions about the Paris attacks.
"They wanted to make some last-minute changes to the debate. We obviously wanted to keep the format to what had been agreed to and I think people on our staff argued vigorously to that and were successful," Weaver told CNN.
"We ended up prevailing," said Weaver, who added that Sanders went over Paris-specific questions Saturday morning.
Weaver and Sanders' top campaign aides feel that while Clinton is very qualified on foreign policy, Sanders will still be able to draw a contrast with her.
"Look, she has far more experience on foreign policy but I think if you look at who has the judgment on foreign policy, we will see who prevails," Weaver said.
Weaver also argued that the terrorist attack doesn't change the tone of the contest.
"I don't think it tempers the tone of the debate," Weaver said. "We are going to have a debate on a wide range of issues."
He added: "I think we are going to carry on the debate we planned to carry on."