The gloves are off in the Democratic presidential campaign, as Joe Biden's main competitors shed the collegiality of the race's early stages to try to knock the former vice president off his front-runner's perch.
Biden was nowhere near San Francisco this weekend for the first major gathering of Democratic hopefuls. But his presence was felt in the Moscone Center as Bernie Sanders, Elizabeth Warren and Pete Buttigieg took unmistakable jabs at his core pitch as a moderate who'll revive to governing by consensus-building.
Sanders told the California Democratic Party convention that there can be "no middle ground" when it comes to delivering on promises of universal health care, addressing climate change, bridging income inequality and assuring abortion rights.
"We will not defeat Donald Trump unless we bring excitement and energy into the campaign, and unless we give millions of working people and young people a reason to vote," said the Vermont senator, who is running second in every recent public poll and has suffered the biggest erosion of support since Biden entered the race. "We cannot go back to the old ways, we have got to go forward with a new and progressive agenda."
Until this weekend, Democratic candidates had mostly avoided criticizing each other. But Biden shifted the dynamic of the campaign when he entered the race in late April. He has been able to build on his name recognition, goodwill from his service as President Barack Obama's vice president and belief among a sizable portion of Democratic voters that he has the best chance to defeat President Trump in 2020.
He has defied expectations among some Democrats by building a strong campaign organization and avoiding, so far, the kind of gaffes that marked much of his career. That's given him a growing and persistent lead in national and many state polls. His rivals now can't afford to let him ride that into the Iowa caucuses that kick off the nomination contest nine months from now.
Video: The California State Democratic Convention played host to a sprawling field of 2020 presidential candidates who got an early opportunity to make their pitch to delegates and activists. (The Washington Post)
Biden is also the biggest threat to the progressive wing of the party that argues voters will be energized by big ideas and sees a chance to push through sweeping policy changes after the next election.
Warren, a senator from Massachusetts who competes with Sanders for the mantle of progressive leader, took aim at what Biden's critics say is his incremental approach to policy and a readiness to compromise. In New Hampshire last month Biden said he believed Republicans will have "an epiphany" once Trump leaves the White House and politics in Washington will "fundamentally change."
"Some Democrats in Washington believe the only changes we can get are tweaks and nudges," Warren said Saturday. "If they dream at all, they dream small. Some say if we'd all just calm down, the Republicans will come to their senses. But our country is in a time of crisis. The time for small ideas is over."
Buttigieg, the 37-year-old mayor of South Bend, Indiana who is staking his candidacy on generational change, warned the Democratic crowd that Trump will win reelection if "we look too much like Washington."
"He wins if we look like more of the same, which means, surprisingly, that the riskiest thing we could do is to try to play it safe," he said. "There's no going back to normal right now."
The increasing attacks by Biden's rivals represent a shifting strategy on how to handle his solid lead at this stage of the campaign. The next big test will come later this month at the first round of Democratic debates, which will be the first time Biden will be on stage with other candidates.
Some of Biden's rivals depict him as a successor to other Washington insiders who have been nominated by the party and lost, including Hillary Clinton, John Kerry and Al Gore.
"There's a long history in both the Republican and Democratic Party of selecting consensus Washington favorites to carry the nomination and who ultimately fail in the general election," said Sanders campaign manager Faiz Shakir. "It should be a note of caution to all pundits who have a firm sense that this 'safe choice' is the choice that voters will go with."
The goal is to foment doubt among voters about Biden's electability, which has been one of his strengths.
"He's old money. He's not fresh," said Ashley Pellounchoud, a 35-year-old attorney in San Francisco. "He can't beat Donald Trump."
Biden skipped the convention to give remarks at a Human Rights Campaign gala in Columbus, Ohio, where he spoke in support of the Equality Act and criticized the Trump administration's policies for the LGBTQ community. The Biden campaign did not comment on the remarks by his rivals, but ahead of the convention, it rolled out an endorsement from Hilda Solis, labor secretary under Obama and a former California congresswoman.
Acting California Democratic Party Chair Alexandra Gallardo-Rooker addressed Biden's absence on Sunday, telling the crowd of delegates that he had called her this week and said he would be visiting California many times in the coming months.
But anti-Biden sentiment was palpable throughout the convention, where delegates expressed frustration with both his candidacy and his absence. One progressive group, Action for a Progressive Future, even distributed fliers that featured quotes from Biden and criticisms of his record.
"The emerging concern has not only been with Biden's record but also his refusal to show up and even speak or engage with anybody at the largest Democratic Party convention before the national one a year from now," said Norman Solomon, the national coordinator of the group and a Sanders supporter.
Yvette Flores, a 19-year-old Sanders supporter, said she thought it was disrespectful that Biden did not attend the convention, and she applauded the candidates for criticizing him.
"Everything he stands for is against the interests of the working class and young Democrats," she said about Biden. "He should be here advocating for the values of the progressive people who live in this state."
This article was written by Sahil Kapur and Tyler Pager, reporters for Bloomberg.