IOWA CITY, Ia. — Sen. Bernie Sanders must do only one thing to hold onto Jim Witte's support in the 2020 Iowa Democratic caucuses.

"Just be himself," Witte said. "Just be honest like he always has been."

A 71-year-old retired truck driver from Dumont, Ia., Witte drove more than two hours to see Sanders at the University of Iowa Memorial Union Friday evening. He arrived four hours before the event to snag a standing spot directly in front of the stage.

Sanders, an independent senator from Vermont, kicked off his second Iowa campaign this weekend with the same fervent support that defined his last run. At rallies in Council Bluffs, Iowa City and Des Moines, the 77-year-old made clear he intends to highlight the same issues that defined his 2016 bid. But he also signaled his commitment to adjusting his strategy and correcting some of the missteps from his past campaign.

While Sanders’ rhetoric largely echoes that of his previous run, he began his Iowa effort miles ahead of where he began before the 2016 Iowa caucuses. He swept through Iowa as a frontrunner: He trails only former vice president Joe Biden, who has yet to declare a run, according to a Des Moines Register/CNN/Mediacom Iowa Poll released this week.

'We love you, Bernie'

At every stop, he railed against Wall Street.

He criticized billionaires and big corporations like Walmart and Amazon.

And he jabbed his right hand into the air, pointing in revulsion as he talked about the high costs of prescription drugs, the criminal justice system and the state of campaign finance.

"Iowa, you helped begin the political revolution in 2016," he told a crowd of 2,000 in Council Bluffs Thursday, "and with your help on this campaign, we’re going to complete what we started here."

It’s unclear whether Sanders can recapture the magic of his 2016 insurgency campaign as he competes within history’s most crowded and diverse field of Democratic candidates. But his events across Iowa this weekend demonstrated that his political movement remains alive with many people reporting their commitment to caucusing for Sanders — a key advantage some 11 months away from caucus night.

He's so far earned the largest crowd counts among visiting caucus candidates in Iowa — his smallest event drew 1,356 people in Des Moines — and they've been filled with people sporting Bernie-branded hats, shirts and scarves.

“Thank you for running,” yelled one man in Council Bluffs as Sanders was just winding up for what would be a nearly hourlong speech Thursday evening.

"We love you, Bernie,” interrupted another.

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Sanders takes on big ag in Iowa

Sanders’ three Iowa events featured the same blue signage as three years ago. The soundtracks were similar with Steve Earle’s "The Revolution Starts Now," and Simon & Garfunkel’s "America" setting the tone.

Many supporters even wore the same sky blue T-shirts they acquired from the last campaign.

Unlike in the early days of his upstart 2016 campaign, every Sanders event in the 2020 cycle brought teams of staffers, professional events managers — even security guards wearing suits and headpieces who escorted him around the crowds of people.

Each Iowa event began with a warm-up musical act from a local band or artist. And at the Iowa State Fairgrounds — at an indoors venue — staffers had adorned the stage with bales of hay.

Even the senator's stump speech revealed nuanced adjustments.

At all three Iowa stops, he made a point to discuss the need to improve childcare access and provide universal preschool — a message that echoes rival Massachusetts Sen. Elizabeth Warren's platform. He's also added talk about the many crises facing rural residents in Iowa and his home state of Vermont. He lamented vanishing schools, hospitals and nursing homes in rural areas.

"I pledge to you to do everything I can to restore the well-being of rural communities all across the country," he said Friday.

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Sanders connected his longstanding disdain of big corporations with the state of Iowa's agricultural industry.

He chided the CEO of Smithfield Food's parent company for reportedly earning $291 million in 2017. While executives get rich, he said the livestock farmers who lease animals and equipment from giant agribusiness firms earn "an inadequate wage for doing extraordinarily hard work."

Sanders said the federal regulators haven't been tough enough with anti-trust enforcement; he specifically criticized the $66 billion Monsanto-Bayer merger for concentrating the seed corn market.

The senator said Iowa's independent pork producers have been put out of business and slaughterhouse employees have suffered through three decades of stagnant wages.

"Meanwhile, instead of protecting family-owned farms, federal support of agriculture is skewed toward large factory farming," he said. "The top ten percent of farms currently get 77 percent of all subsidies."

Unlike many of the other candidates who have visited Iowa in recent weeks, Sanders took no questions from the crowds or the media at his events.

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Sanders acknowledges 'valid criticisms' from 2016

Sanders enters the race with the luxury of name recognition. And after 100 Iowa campaign events in 2015 and 2016, he said he believes many Iowans understand his policy positions.

"Having said that, there are a lot of strong candidates who are running," he said in an interview with the Des Moines Register on Thursday. “Last time, I had one opponent, now I’ll have ten or fifteen opponents. And my job is to convince the people of Iowa that I am, in the caucuses at least, the strongest candidate to defeat Donald Trump. And I think I am.”

On the stump, Sanders takes credit for transformations within the national Democratic party. Ideas like a $15 minimum wage, free college and Medicare-for-all were considered "radical," he said, but are now mainstream in the party.

"I'm proud of that and I think all I would ask of Iowans is check my record," he said in the interview. "Find out who was talking about those issues when it wasn’t so easy to talk about it, when those ideas were not so popular."

Sanders will continue to hold large, rowdy rallies. But he said he also wants to carve time to meet with smaller groups. Sanders said he wants to hear the individual concerns of female, Latino, black and older Iowans.

To that end, Sanders held off-the-record meetings Friday with volunteers and dropped by Des Moines' Southside Senior Center.

The senator says he will also talk more about his personal narrative — a major change for a candidate who despises personality politics. While his national campaign kickoff events in Brooklyn and Chicago included heavy doses of biography, he didn't employ that strategy much on his first Iowa swing.

He kept primarily to the issues during his first two stops, though in Des Moines he referenced his family's working-class background and contrasted that with Trump.

"My family knew what it's like to live paycheck to paycheck," he said. "I know where I come from, and I will never forget that."

Sanders acknowledged the criticism of his 2016 campaign for being too male-oriented and too white.

Since then, he's realigned much of the top brass and has hired ACLU national political director Faiz Shakir as his national campaign manager.

In Des Moines, two immigrants introduced Sanders, including Vanessa Marcano Kelly, who is originally from Venezuela and who became a U.S. citizen two days prior.

"I think those were valid criticisms," the senator told the Register. "And I think what the people of America will see in this campaign is a much more diverse campaign in every sense of the word. And I think that’s the right thing and a good thing."

Sanders must pivot from 'binary' race to a 'wide open' one

For most potential caucusgoers, the race remains "wide open," said Brian Bruening, chairman of the Clayton County Democrats, which hosted Warren earlier this month.

Bruening, who said he didn't know any Democrats in his eastern Iowa county who had committed to 2020 candidates, said Sanders needs to reintroduce his ideas to Iowans.

"It’s a different game now," Bruening said. "It was a binary decision back in 2016 in a lot of ways. And now it’s not."

Gabe Lozano, a 37-year-old Iowa State University student who attended Sanders' Des Moines rally, said he appreciates that the senator has been advocating for things like Medicare-for-all and combating climate change "since before it was cool."

"As early as it is, I do want to keep an open mind," he said. "But at this point, it seems like he has the best shot."

Lozano said he also likes Warren and her history of taking on the big banks and government corruption, but he worries that she doesn't have as much support as Sanders and would be less electable.

"Hopefully, it’s Bernie Sanders and Elizabeth Warren, because we’re winners either way in that situation," he said. "I’m just hoping it gets to that point where she can build the momentum he has, that way it can get to that point where they’re the two most popular candidates."

People like Cyndie Poffenbarger needed no convincing.

"I followed him for like 10 years before he ever ran for president," she said after a Sanders rally in Council Bluff's Mid-America Center. "I've always admired Bernie Sanders."

Wearing a "Bernie 2016" cap and a "Bernie 2020" T-shirt, Poffenbarger said she believes Sanders is best equipped to defeat Trump.

"Because he's honest," said the 64-year-old hospital accounting specialist from Council Bluffs. "More people know him this time."

Marc Mohn, a 62-year-old utilities technician at the University of Iowa, said he doesn’t want to see any changes from Sanders’ 2016 campaign.

"I like his message," he said.

Mohn caucused and volunteered for Sanders three years ago and plans to do so again. He believes the senator would have defeated Trump in 2016 and thinks he can beat him in the 2020 general election.

Upon entering the Memorial Union's Main Lounge Friday evening, Mohn ducked behind a wooden partition for a wardrobe change. He emerged in a well-worn blue T-shirt he picked up before the 2016 caucuses.

The front features a hand-drawn sketch of Sanders on stage. The back reads "Forever Bernie."