Bernie Sanders, Hillary Clinton, and Martin O'Malley at the Democratic debate in November Charlie Neibergall / AP

The Democratic presidential candidates will face off on the debate stage again on Saturday at a time when national security has renewed importance following the San Bernardino attacks.

But overshadowing the debate is the tension between the candidates and the Democratic National Committee, which was most recently put on display on Friday. On the eve of the debate—which will be held in Manchester, New Hampshire, at 8 p.m.—Bernie Sanders’s team accused the DNC of sabotaging the campaign hours after the committee denied the camp access to a crucial voter database. The DNC said that Sanders’s campaign had improperly accessed Hillary Clinton’s private campaign data.

“We are announcing today if the DNC continues to hold our data hostage and continues to attack the heart and soul of our grassroots campaign, we will be in federal court this afternoon seeking immediate relief,” said campaign manager Jeff Weaver at a news conference. “What is required here is a full and independent audit of the DNC’s mishandling of this data and its security from the beginning of this campaign to the present.”

Friday’s events added to a list of grievances the candidates have brought against the committee. Martin O’Malley has continually complained about the party’s debate schedule, which has so far had two fall on Saturday nights. “They’ve scheduled it during shopping season, December 19,” O’Malley said. “I don’t know why that is.”

The strained relationship between the candidates and the committee is likely to frame the context of the debate, as Sanders’s supporters question the national committee’s intentions. As my colleague Clare Foran put it:

The next Democratic debate is set to take place on Saturday, a time slot that has led to speculation among Sanders supporters that the Democratic establishment is actively trying to discourage viewership. It has fed suspicion that the party is attempting to coronate Clinton. That fear is sure to intensify if the fight between the Sanders campaign and the DNC escalates.

Sanders has been pulling ahead in New Hampshire, presenting himself as a challenge to Clinton. Earlier this month, a WMUR/ CNN poll showed 83 percent of presidential primary voters in the state viewed Sanders favorably in comparison with Clinton’s 68 percent. Nationally, however, Clinton is still maintaining her lead. A Washington Post/ABC News poll revealed that 59 percent of Democratic-leaning registered voters support Clinton compared with the 28 percent supporting Sanders. Meanwhile, O’Malley is in the single digits at 5 percent.

On Saturday, the three Democratic presidential candidates will also likely be tasked with fielding questions on national security. Concerns about terrorism have heightened following the San Bernardino attacks earlier this month, shifting the dialogue on the campaign trail to national security. Just this week, Democratic front-runner Clinton outlined her plan to defeat ISIS. Clinton, Sanders, and O’Malley have confronted the subject before. The last Democratic debate, which was held in Iowa, took place a day after the Paris attacks.

The emphasis on foreign policy then played to Clinton’s strengths. Candidates fielded questions about the terrorist group and mostly highlighted that the fight is not with Islam but with violent radicals. Sanders, however, appeared uncomfortable, instead attempting to pivot to domestic issues.

Much of the same can be expected now. While Clinton may be more seasoned on the subject as former secretary of state, she, too, is in a difficult position. She’ll be expected to support the White House’s initiatives—President Obama has spoken at length on the topic—and also to distinguish herself. Sanders will again have to deviate from a campaign that has been mainly focused on the economy and has yet to clearly define what he would do about ISIS. Meanwhile, O’Malley’s challenge is to get some exposure and make himself relevant as he struggles in the polls.

After Saturday’s debate, there is one more debate scheduled before the Iowa caucuses and New Hampshire primaries.

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