Story highlights Between votes, Ellison's camp sent a text to members claiming incorrectly that a candidate who dropped out had endorsed him

Ellison's and Perez's supporters clashed throughout the months-long process

ATLANTA (CNN) Progressive activists lashed out at the Democratic Party on Saturday after their choice to lead its national committee, Minnesota Rep. Keith Ellison, was defeated by former Obama administration Labor Secretary Tom Perez in a tight and unexpectedly contentious contest.

After the results were announced, angry Ellison loyalists rose from their seats in the back of the ballroom at the Westin Peachtree Plaza Hotel and tried to shout down outgoing interim chair Donna Brazile, chanting, "Party for the people, not big money!"

"This shows that the Democratic Party didn't learn their lesson," said Alexa Vaca, an Ellison backer and supporter of Vermont Sen. Bernie Sanders during the party's divisive 2016 primary race. "They are not going to be in touch with the people and they are not ready to move in a new direction despite the rhetoric."

The race for Democratic National Committee chair, normally a quiet affair managed by party insiders, emerged as a roiling public campaign, as progressives loyal to Sen. Bernie Sanders and establishment Democrats jousted for control of a depleted organization increasingly at loose ends after eight years in the White House and then Hillary Clinton's unexpected loss to Donald Trump.

In the run-up to the vote, both candidates had liberal luminaries making calls to members on their behalf. Sanders and New York City Mayor Bill de Blasio, who spent the last two days in Atlanta, actively stumped for Ellison. On Perez's side, former Vice President Joe Biden and longtime Obama confidant and adviser Valerie Jarrett worked the phones.

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