ASSOCIATED PRESS/J. Scott Applewhite Sen. Bernie Sanders has yet to decide whether he will run for president in 2020.

BROOKLYN, N.Y. ― Supporters of Sen. Bernie Sanders (I-Vt.) held over 400 house parties in all 50 states and Puerto Rico on Saturday afternoon calling on Sanders to run for president again in 2020.

Sanders maintains that he is still considering whether he is the best person to defeat President Donald Trump.

But Saturday’s show of force, arranged by Organizing for Bernie ― an upstart group founded by Sanders campaign alumni and grassroots activists ― demonstrated one of the senator’s biggest advantages if he decides to return to the ring: a network of supporters already familiar with his message and skilled in do-it-yourself internet organizing.

Speaking to the house parties by livestream, Kat Brezler, a Bronx public school teacher and co-founder of the group People for Bernie, called on the participants to use social media to show Sanders the scale of his support with the hashtag RunBernieRun.

“We need to convince Bernie Sanders to run. He isn’t in this race yet,” Brezler said.

Emphasizing the policy stakes of Sanders’ bid, Brezler added, “We need ‘Medicare for all,’ we need tuition-free college and we need to abolish [Immigration and Customs Enforcement], end mass incarceration, [enact national marijuana] legalization and all of the other reasons why we come to this movement.”

Although Sanders and his campaign team were not directly involved in Saturday’s events, the house parties were co-sponsored by People for Bernie and Our Revolution, the latter group created to carry on the mission of Sanders’ 2016 campaign.

The livestream, which was broadcast by progressive media upstart Act.tv, had attracted over 100,000 views as of Saturday evening.

The broadcast aimed to push back against a narrative developing in the media that Sanders would have difficulty retaining his 2016 staff, as well as to pre-emptively refute questions about the diversity of his staff and surrogates in a hypothetical 2020 run. In addition to Brezler, the speakers included Nina Turner, president of Our Revolution, and RoseAnn DeMoro, former executive director of National Nurses United. The discussion also featured contributions from Roy Tatem, the former deputy director of Sanders’ 2016 African-American outreach; Cori Bush, an African-American nurse and former progressive congressional candidate; and Belén Sisa, an undocumented immigrant activist and former member of Sanders’ Latino outreach team.

Tatem, president of the East Valley NAACP in metropolitan Phoenix, argued that a second Sanders campaign would have greater success in reaching the middle-aged and older voters of color who proved so elusive for Sanders in 2016. The senator would no longer struggle to merely establish name recognition with these voters and inform them about his progressive platform, according to Tatem.

“Now everybody knows who Bernie Sanders is and about his program for free college, health care for all and actually dealing with police violence,” he said. “I encourage people to take a look at our racial justice platform in 2016. I’m hoping that we have a campaign so we can really talk about [that].”

As Sanders, 77, deliberates whether to toss his hat in the presidential ring, other Democratic candidates are rapidly jumping into the race.

Sen. Elizabeth Warren (D-Mass.), who would very likely be the field’s second-most progressive contender after Sanders, announced her bid on New Year’s Eve. Rep. Tulsi Gabbard (D-Hawaii) joined the field on Friday. And former Housing and Urban Development Secretary Julián Castro launched his campaign on Saturday.

Even though Bernie has not announced yet, the opposition certainly has. RoseAnn DeMoro, former executive director for National Nurses United

Meanwhile, Sanders is undergoing scrutiny for complaints that senior figures in his 2016 campaign did not appropriately deal with sexual harassment among campaign staff. Earlier this month, The New York Times reported that some former staffers wanted an opportunity to confront Sanders about the lack of attentiveness to harassment issues, as well as alleged gender pay disparities among the staff. On Thursday, Politico also revealed that Robert Becker, a former top Sanders field staffer, was accused of forcibly kissing a subordinate.

Amid pressure to demonstrate that a 2020 campaign would not repeat the same mistakes, Sanders’ former campaign manager, Jeff Weaver, announced Wednesday that he would not be returning in that role for a second run. Sanders has also apologized for the mistreatment of some women and promised that his campaign team has already taken steps to improve.

In Saturday’s livestream, Sanders allies applied a dual approach to addressing the controversy. On the one hand, DeMoro implied that some of the negative stories were the product of ideologically driven efforts to undermine Sanders.

“Even though Bernie has not announced yet, the opposition certainly has,” said DeMoro, one of the only national labor union leaders to back Sanders in 2016. “They’re not trying to take Bernie out; they’re trying to take the movement out.”

At the same time, Sheila Healy, who worked on Sanders’ successful 2018 Senate re-election, told supporters that his campaign had implemented much tougher measures to prevent future workplace issues.

Healy noted that the Senate campaign had created a human resources hotline which employees could use to report harassment without fear of retaliation or discomfort, provided mandatory sexual harassment training to all staff and volunteers, and made sure that the signs explaining the campaign’s anti-harassment policy were posted visibly in all areas.

“I can say with certainty, if the senator does decide to run, these new policies are going to remain in place in 2020,” she said.

We don’t know if they can beat Trump. We pretty much know Bernie can beat Trump. Amber Watson, speaking of other potential Democratic candidates

In Lindsey Ullman and Charles Frantz’s stylish two-bedroom apartment in Brooklyn’s Bushwick neighborhood, about 20 hardcore Sanders fans gathered to watch the livestream over pizza, beer and LaCroix. Following the recommendations of the livestream organizers, they subsequently discussed strategies for improving on Sanders’ impressive but ultimately failed 2016 performance.

Ullman, a graphic designer, and Frantz, a software engineer, knew only two of the attendees beforehand. The people who had signed up for their gathering through the Organizing for Bernie website now displayed their names and preferred pronouns on name tags.

The crowd skewed younger and whiter with a roughly even gender balance. About half of those present were active in the Democratic Socialists of America, a dues-paying organization that saw its ranks explode in the wake of Sanders’ 2016 run.

Some of the partygoers were convinced that Sanders needed to run because he was the most electable candidate in a head-to-head matchup against Trump.

Referring to other candidates, Amber Watson, a sound engineer, said, “They haven’t run in any presidential elections.”

“We don’t know if they can beat Trump,” she said. “We pretty much know Bernie can beat Trump.”

Referring to 2016 Democratic presidential nominee Hillary Clinton, Russell Whitehouse, a progressive activist and internet entrepreneur, said, “It didn’t work last time. We ran a centrist last time.”

But other attendees simply believed that Sanders is the politician most authentically committed to enacting Medicare for all, free college and the dramatic measures needed to combat climate change.

“What matters is the policies,” said Andy Simpson, a Manhattanite who crossed the East River to attend the party.

Asked about other rumored contenders’ adoption of some of Sanders’ core policy positions, like Medicare for all, Dave Crumbley, a standup comic visiting from Ohio, replied, “It’s lip service.”

“The fact that Bernie is the only candidate who could inspire this kind of gathering says it all,” Ullman said.

Frantz offered one caveat: If Rep. Alexandria Ocasio-Cortez (D-N.Y.), a former Sanders organizer, were 35 years old ― and thus eligible to serve as president ― she might be capable of generating the same level of enthusiasm.

“If she were 35 years old, this party would be for her,” Ullman interjected. The other partygoers laughed with approval.