The enthusiastic support that fueled Bernie Sanders’ insurgent bid for the Democratic nomination in 2016 does not appear to have waned heading into the 2020 race.

The Vermont senator officially got back on the campaign trail Thursday, beginning a trip across Iowa with a large, boisterous rally in Council Bluffs – a small city at the westernmost end of the key caucus state, just across the border from Omaha, Nebraska.

Here in the Hawkeye State, where presidential aspirants drop in every four years to pitch themselves to voters, it’s common practice to kick the tires a little bit – to check out an array of candidates as they make their way through town. But that didn’t appear to be the case in Council Bluffs, where those who turned out to see the firebrand independent largely seemed set on showing their support for the man they say is the most “authentic” champion of progressive causes in the crowded field.

“All his ideas they said were radical, they’re embracing them now,” Bob Jordan, a resident of Council Bluffs, said after the rally. “[The other candidates] are jumping on the bandwagon.”

Quick guide Who are the leading Democrats running for 2020? Show Hide Joe Biden, former vice president Biden unsuccessfully ran for the nomination in 1988 and 2008, and his campaign is likely to be dogged by controversy after allegations from several women they were left feeling uncomfortable by their physical interactions with him. If successful, Biden would become the oldest person to be elected president in US history. Mike Bloomberg, former New York mayor Bloomberg has expressed concern that none of the top candidates can defeat Trump, and he aims to make up for an unusually late entry in the Democratic primary with historic spending of hundreds of millions of dollars in television ad time and an unorthodox strategy of skipping the first four states in the primary. Bloomberg has announced that his campaign will be entirely self-funded, but can this billionaire win? Amy Klobuchar, Minnesota senator On Election Night 2018, Klobuchar coasted to a third term as senator in a state Trump almost won. Next morning she was on every short list of potential presidential candidates. Supporters say her success with rural voters makes her a formidable candidate in the Rust Belt, while her calm demeanour provides a clear contrast with Trump. Bernie Sanders, Vermont senator Sanders turned a long-shot, anti-establishment bid for the presidency into a “political revolution” that energized the party’s progressive base. His political career began nearly 40 years ago, but it wasn’t until his 2016 run that Sanders became a national figure as a new generation of Democrats – and 2020 contenders – embraced his populist economic policies. Elizabeth Warren, Massachusetts senator Her sharp criticism of Wall Street and big corporations has made Warren a favorite among progressive activists, and she will campaign on a message of a rigged economic system and income inequality.

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The energy at the Mid-America Center Thursday recalled the movement that surrounded Sanders’ campaign in 2016 – and suggested that the momentum he built could carry over into the current cycle.

“I didn’t think I was going to be a Bernie supporter, but he said a lot of things that appealed to me,” said Joan Minikus, Jordan’s wife, who supported Hillary Clinton in 2016. “He has an awesome message.”

Sanders mostly played the hits Thursday night, focusing on his signature message of economic populism and social justice and calling for sweeping changes to the American political system.

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“It’s not only that we’re going to win the Democratic nomination. It’s not only that we’re going to defeat Donald Trump, the most dangerous president in modern American history,” Sanders told a cheering crowd. “With your help, we’re going to transform this country and create an economy and a government that works for all of us, not just the 1%.”

That message resonated with his supporters here, where he said his “political revolution” began in 2016.

“He’s the only one that tells it like it is,” Joe Driscoll, a farmer who came to see Sanders from nearby Honey Creek, Iowa, said.

Sanders was edged out in Iowa by Clinton in 2016, but now enjoys perhaps the largest national profile of any of the Democrats who have officially entered the fray so far. He’s performed well here in early polling, and has posted extraordinary fundraising numbers since launching his latest campaign. Sanders, Senator Kamala Harris, and the former vice-president Joe Biden – who has yet to officially enter the race – appear to be leading the crowded pack of Democratic candidates so far.

Sanders also faces some obstacles. He struggled last election to appeal to black voters; if that struggle continues, it could spell doom for the 77-year-old in a cycle where Democrats increasingly appear to be looking for fresh faces that better reflect the party’s diversity. He’s also facing a different political landscape than he was in 2016 – one in which some of his signature policy positions are being championed by his competitors.

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But Shirley Nelson, who supported Sanders in 2016 and came to Council Bluffs from neighboring Omaha on Thursday to see him for the first time, said she can’t be sure if more mainstream Democrats truly support such a progressive platform, or if they are backing such positions because of the momentum Sanders has built behind them.

“He’s been fighting the good fight forever and ever,” Nelson told the Guardian. “I don’t know what [the other candidates] truly feel, but I know how Bernie feels, because time has borne out that truth.”

Not everybody came to the Mid-America Center feeling the Bern. Rahian Kocer is socially progressive, but more moderate fiscally, and parts of the Vermont senator’s democratic socialist agenda concern him. He supported Clinton in 2016 and likes Harris in the early going of the 2020 cycle. But, the Council Bluffs resident said, the most important thing to him is defeating Trump – and he’ll support whichever Democrat gets the party nod.

I’m here with an open mind,” Kocer said ahead of the event.

But his friend, Ashley Barrett, doesn’t share his reservations about Sanders. She “loves what he stands for” – so much so that she got her boyfriend, William Dunn, who supported Senator Ted Cruz in 2016, to come with her to the rally.

“I love Bernie Sanders,” she said.

