SAN FRANCISCO (CN) – President Donald Trump wasn’t on the agenda at Friday’s summer meeting of the Democratic National Committee, but the party’s 2020 hopefuls injected him into the top of it anyway.

An assortment of leading Democratic presidential candidates lined up to remind party leaders and delegates that they believe Trump is morally bankrupt and unfit for a second term. They made it abundantly clear to attendees that the White House will continue to drive the conversation as the Democrats stump for the 2020 primary.

During a forum in downtown San Francisco, Vermont Senator Bernie Sanders called Trump “the most dangerous president in American history” who panders to “xenophobes” and “white nationalists.” Minnesota Senator Amy Klobuchar called him a “whiner,” while the latest Democratic entrant in the race, billionaire Tom Steyer, painted Trump as a “swamp rat” and a fraud.

But California Senator Kamala Harris was the most blunt. She spent several of her eight minutes eviscerating the president for having a “fragile ego” and accused his administration of greenlighting human rights abuse at the border. She then tied Trump to the recent mass shooting in El Paso, Texas, that left 22 people dead and another 24 injured.

“Of course he didn’t pull the trigger but he certainly has been tweeting out the ammunition,” Harris told the crowd.

The party confab comes as the Democratic candidates scratch to pull away from each other in the polls ahead of the next batch of debates in September. While Biden has consistently topped national polls since jumping into the race, Harris, Sanders and Massachusetts Senator Elizabeth Warren are within striking distance.

The only major candidate to skip the Trump-bashing session was Warren. She didn’t mention the president by name, instead drumming up support for the variety of economic reforms she’s introduced on the campaign trail, including her so-called “millionaire tax” and getting corporate money out of politics.

“It’s time to overturn Citizens United, democracy is not for sale,” Warren said, referring to the landmark Supreme Court case prohibited the government from restricting political spending by corporations. “This is our chance to walk the walk.”

Attendee Amy Wittens of Los Angeles called Warren’s approach “refreshing” and said she hopes the other candidates were taking notes.

“Her style was different. I think Warren appealed to many who believe the election isn’t just about Trump,” Wittens said.

While a majority of the candidates made the trip to California, the most notable absence was former Vice President Joe Biden. The front-runner also skipped the California Democratic Party convention this summer that was attended by many of the other candidates.

Biden and others who skipped the DNC event, including Pete Buttigieg and Beto O’Rourke, were allowed to show short videos to the crowd in their absence.

After a burst of momentum following the first debate, where she stole the show by blasting Biden on 1970s integration busing policy, Harris’ performance in recent polls has waned. She told the friendly crowd it will take a prosecutor to defeat Trump.

“We’ve got a big long rap sheet to work with,” Harris, the former attorney general of California, continued.

While the candidates took turns on Trump, they also reminded the crowd that unity will be critical for the Democrats in 2020 – no matter who wins the nomination.

“I believe we beat Donald Trump not by being like him, but we beat him like we beat dictators and bullies and demagogues in the past – by coming together and calling to the best of who we are,” said New Jersey Senator Cory Booker.

The candidates piled on a president they see as vulnerable: On Thursday, a poll by The Associated Press found more than 6 in 10 Americans disapprove of Trump’s job performance.

The president’s approval rating has been in the low 40s for the majority of his presidency, particularly in his second and third year in office, though his disapproval rating spiked above 58% at the end of 2017 according to data from RealClearPolitics.

Friday’s festivities saw the crowded Democratic primary field get slightly less crowded. U.S. Rep. Seth Moulton of Massachusetts told the crowd he will drop out of the presidential race to pursue re-election.