The release of more than 19,000 pages of hacked emails from the Democratic National Committee competed on Saturday with the big reveal of Virginia Sen. Tim Kaine as the running mate of presumptive nominee Hillary Clinton.
On Friday, WikiLeaks dropped a bombshell cache of DNC emails. Several weeks ago, Russian hackers were reported to have breached the DNC's servers, but on Saturday WikiLeaks refused to disclose where it had obtained the trove of data.
Among other things, the documents purport to show the party apparatus favoring Clinton's campaign over the insurgency of Vermont Sen. Bernie Sanders. On a number of occasions, high level DNC officials met with counterparts on Clinton's team to discuss ways to push back against stories that painted the Clinton campaign in a negative light.
One pointedly worded missive dismissed Sanders' campaign as "a mess" adding that his campaign apparatus "never had their act together."
The news took center stage on social media, threatening to upend the Democrats' messaging and steal attention from a chaotic and divided Republican National Convention, which wrapped up on Thursday night. The email exchanges may reopen the wounds of a bitter Democratic primary season, just as the party kicks off its own national conference designed to highlight a unified, energized party.
The DNC did not respond to CNBC's request for comment, but Sanders' campaign manager Jeff Weaver told ABC News in an interview that "someone in the DNC needs to be held at least as accountable as the Trump campaign," for a controversy involving Melania Trump's speech earlier this week, Weaver said.
Separately, CNN reported late Saturday that Florida Rep. Debbie Wasserman Schultz, the embattled DNC chair, would be denied a speaking role at the convention in the wake of the leak.
Indeed, only half a day after Clinton announced Kaine as her vice presidential pick, news of the DNC leak was one of the top trending item on Twitter on Saturday.
GOP nominee Donald Trump leaped into the fray to blast Democrats for their perceived treatment of Sanders, calling it "really vicious."
On Saturday, some users accused Twitter of censoring search results of the leak — an accusation Facebook faced several months ago when it came under fire for suppressing conservative-leaning commentary on its site.
The leaked emails revealed in various instances that DNC officials spoke disparagingly about Sanders and his supporters.
In one series of messages on May 7, several party staffers vetted a fundraising email from Clinton's campaign. One appeared to object to draft language that alluded to the possibility that Trump could appoint "Scalia-like" judges to the Supreme Court, and removed the reference. The exchange was unusual, given that at the time Clinton was still locked in a primary battle with Sanders, and had not yet sewn up the delegates needed for nomination.
In another lengthy exchange, party officials appeared to do damage control over reports that a Clinton-controlled fund was walking away with the lion's share of money meant to be used for down-ballot candidates. DNC staffers discussed how to undercut the story, which at the time was being covered widely by news organizations, and appeared to coordinate talking points with the Clinton campaign.
Several other emails suggested the national organization, headed by Wasserman Schultz, was trying to tilt the scales in favor of the former secretary of state. Some showed DNC staffers cultivating political journalists at key broadcast and print outlets to influence their coverage of both candidates.
The DNC has repeatedly denied it favored any candidate in particular. However, a frequent refrain by Sanders' supporters throughout his insurgent campaign was that it was "rigged" by Democrats intent on handing the nomination to Clinton, the clear favorite of the Democratic establishment.
In one message dated May 5, an exchange involving the DNC's finance chief asked a staffer to gather information on Sanders' reported atheist beliefs, suggesting that it could influence the decision of Southern voters. Sanders has alluded to his Jewish ancestry, but hasn't made much reference to religious beliefs during the campaign.
"My Southern Baptist peeps would draw a big difference between a Jew and an atheist," Brad Marshall, the DNC's chief financial officer, said in the email.
On his Facebook page, which was not available to the general public, Marshall said he "deeply" regrets his "insensitive, emotional emails," according to Politico.
For his part, the Vermont senator remained largely silent about the affair. He made no remarks about the controversy on Twitter, where early Saturday he made an innocuous statement about the minimum wage.
Several weeks ago, the senator's supporters threatened a floor fight at the DNC convention in Philadelphia, but support for that was undercut by Sanders' full-throated endorsement of Clinton after he dropped out of the race.
WikiLeaks founder Julian Assange has a widely known antipathy toward Clinton. He's been quoted as calling the former secretary of state a "war hawk" and warned in June that a new leak could damage her candidacy.
Assange has also been sharply critical of President Barack Obama's foreign policy, most notably his administration's use of drones in the Middle East.
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