The 'March for Bernie' at Hermann Park brought together dozens of the Vermont Senator's supporters after a cache of nearly 20,000 DNC emails were released by the Wikileaks.
PHOTO: Demonstrators in Houston protest after new DNC emails emerge
The emails detailed the acrimonious split between the Democratic National Committee and Clinton's former rival, Sen. Bernie Sanders.
Sanders supporters say the emails purportedly show the Democratic Party rigged its nomination process for Secretary Clinton by undermining the challenger's campaign.
The protesters also allege the party attempted to suppress voter turnout by various means, including the scheduling of Democratic presidential debates on Saturdays and against televised sports events.
Leaked e-mails of DNC show plans to destroy Bernie Sanders. Mock his heritage and much more. On-line from Wikileakes, really vicious. RIGGED— Donald J. Trump (@realDonaldTrump) July 23, 2016
Several emails posted by Wikileaks on its document disclosure website show DNC officials scoffing at Sanders and his supporters and in one instance, questioning his commitment to his Jewish religion. Some emails also show DNC and White House officials mulling whether to invite guests with controversial backgrounds to Democratic party events.
Although Wikileaks' posting of the emails Friday did not disclose the identity of who provided the private material, those knowledgeable about the breach said last month that Russian hackers had penetrated the DNC computer system. At the time, DNC Chairwoman Debbie Wasserman Schultz called the breach a "serious incident."
VIDEO: Nomination system rigged against Sanders, supporters say
Wikileaks says the new cache of emails came from the accounts of "seven key figures in the DNC" and warns that the release is "part one of our new Hillary Leaks series" - an indication that more material might be published soon.
The leaked emails include thousands from the party's communication director and more than 3,700 emails from its national finance director.
Some staffers were found emailing about ways to discredit Sanders in favor of a Clinton candidacy.
The emails were sent between January of last year and May of this year, and are part of a new series of emails focused on the Democratic nominee.
Wikileaks founder Julian Assange has long railed against a possible Clinton presidency.
The commotion comes just a day before Clinton and running mate Virginia Sen. Tim Kaine head to Philadelphia for the Democratic National Convention.
The party announced Sunday that Wasserman-Schultz would not speak or preside over the party's convention next week.
The news was welcomed by Sen. Sanders, who has pushed for Wasserman-Schultz's ouster after perceived bias throughout the primary and caucus season.
Sanders says the emails did not come as a "great shock."
"I mean, there's no question to my mind and I think no question to any objective observer's mind that the DNC was supporting Hillary Clinton and was in opposition to our campaign."
Sanders also said he would continue to push for the resignation of Wasserman-Schultz from the DNC.
Surrogates for the DNC and Clinton's campaign spent the day combating the perceptions of Sanders supporters on the morning talk shows.
Robby Mook told CNN Sunday morning that Russian hackers are behind the attack on DNC email servers.
VIDEO: Bernie Sanders makes campaign stop in Houston
"I think the DNC needs to look into this and take appropriate action, and I'm sure that they will," Mook says.
"What's disturbing to us is that we... experts are telling us that Russian state hackers broke into the DNC, stole these emails and... other experts are now saying that they are, the Russians are releasing these emails for the purpose of actually helping Donald Trump."
Meantime, Baltimore Mayor Stephanie Rawlings-Blake, who also serves as DNC secretary, says the Wikileaks release isn't anything that hasn't been seen at the Republican Party.
VIDEO: Baltimore mayor denies DNC rigging for Hillary
"Donald Trump is grasping at straws. I think the e-mails, while not verified, suggest the same thing that happened at the Republican party," Rawlings-Blake says.
"There's no person that's engaged in politics that doesn't have an opinion about politics. Expressing an opinion about a candidate doesn't mean that you're in collusion, doesn't mean that you are actively working against them. And i don't think that that's what it shows."
In a brief response, Donald Trump Jr., defended his father, stating "they'll say anything to be able to win this."
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