At the start of the 2020 campaign, many Democrats have disavowed donations from corporate PACs and are emphasising the importance of small-dollar donations, an early litmus test of strength and grass roots energy in a crowded field.

With Sanders’ entry in to the race on Tuesday, 12 candidates are now seeing the Democratic nomination – with decisions expected to follow from former vice-president Joe Biden, former Texas congressman Beto O’Rourke and former New York City mayor Michael Bloomberg.

Sanders, who has near-universal name recognition and one of the largest fundraising lists in US politics, raised far more than many of the other 2020 candidates after their campaign launches.

By comparison, Senator Kamala Harris raised more than the US$1.5m in the first 24 hours of her campaign. Harris had been the biggest first-day fundraiser in the race so far and matched what Sanders’ raised in April 2015 after he launched his bid for the nomination that year.

Meanwhile, Minnesota senator Amy Klobuchar’s campaign said she raised more than US$1m in the 48 hours after launching her presidential bid this month.

Sanders, a self-styled Democratic socialist who spent much of his nearly 30-year congressional career on the political fringe, launched his campaign on Tuesday morning, casting his candidacy as the best way to accomplish the mission he started four years ago when he ran against Hillary Clinton for the Democratic nomination.

“Together, you and I and our 2016 campaign began the political revolution,” he said in an email announcing his decision to supporters. “Now, it is time to complete that revolution and implement the vision that we fought for.”

Sanders, 77, running as a Democrat again, believes he can prevail in a crowded and diverse field that includes several female and minority candidates, and then beat Donald Trump, whom he called on Tuesday “the most dangerous president in modern American history”.

The progressive policies Sanders helped popularise in 2016 – Medicare for All, a US$15 an hour federal minimum wage, tuition-free college, demands to fight climate change more aggressively and to tax the wealthy at a higher rate – have now been broadly embraced by several other presidential candidates.

Asked in an interview on CBS on Tuesday morning what would be different about his 2020 campaign, Sanders replied: “We’re gonna win.”

However, whether he can once again capture grass roots support, and whether the energy of his past campaign will pass to other candidates, is likely to be a central factor in determining who Democrats nominate to take on the sitting president at the next election.

His campaign believes his initial fundraising haul is an early sign that he can.

A series of early Sanders hires for top roles are intended to illustrate his campaign’s commitment to demographic and geographic diversity.

Faiz Shakir, the political director of the American Civil Liberties Union, will serve as campaign manager. The 39-year-old former aide to Harry Reid will be the first Muslim to manage a presidential campaign.

The campaign also hired Analilia Mejia, the progressive organiser and former executive director of the New Jersey Working Families Alliance, to be the political director and Sarah Badawi, the former government affairs director for the Progressive Change Campaign Committee, to be her deputy.