I thought Bernie's Iowa numbers seemed unrealistically high. Then I saw his rallies

Three political rallies in a small north-west Iowa town over the weekend convinced me that the polls showing Bernie Sanders leading among likely caucus-goers have it about right.

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Some 400 people packed into a ballroom in Storm Lake, Iowa, on Sunday to hear Michael Moore, Alexandria Ocasio-Cortez and the disheveled senator from Vermont raise the roof for a political revolution.

Polls going into the weekend showed Sanders with 25% of the likely crowd at the caucuses on 3 February. Joe Biden, Pete Buttigieg and Elizabeth Warren trail closely, while Amy Klobuchar is building support late and Andrew Yang is getting some interest.

Bernie had momentum on Sunday. People were hooting and hollering and clapping for Moore, the documentarian, when he said the rich will have a harder time getting to heaven than a camel through the eye of a needle. He cited Paul’s letter to the Corinthians urging unity over factionalism. The revival meeting lapped it up.

The night before, Buttigieg appeared at Buena Vista University to a crowd of 220 with half the enthusiasm of the Sanders affair. He spoke about healing wounds, too, but nobody was going wild. His biggest applause line came when he complained that “everybody needs a second job”.

After Sanders’s rally in the afternoon, Yang made his first appearance in Storm Lake to a crowd of about 100. He had them laughing, and got them worrying about artificial intelligence eliminating 40,000 manufacturing jobs in Iowa. Truckers may be a thing of the past. It got everyone’s attention. The New York businessman has his facts and figures – that Amazon wiped out 30% of our state’s retail business, and that the erosion of local news is undermining democracy – down into a compelling narrative about how capital and technology conspire to leave huge swaths of America behind.

Yang’s solution, as articulated, is to give everyone $1,000 per month, and to take back democracy. He thinks he can “rewire the economy” to bring something back to those lost places in the swing states where jobs, people and prospects keep getting drained to the coasts.

“We are in the midst of the greatest economic transformation in our nation’s history,” Yang said to his largest applause.

In fact, that may explain why Sanders is leading.

“We’re going to win because working people are tired of being ignored, working two or three jobs,” Sanders proclaimed to heads nodding and amens.

The ballroom echoed in boos when Sanders detailed how 12 years ago “Congress bailed out crooks on Wall Street, and then Trump gave them a trillion dollars in tax breaks”. And Amazon pays no tax. Boo!

A man up front said his health insurance premiums are $1,400 per month.

Sanders said that the average $60,000 household in Iowa would pay that much per year on healthcare taxes with Medicare for All. No premiums. No deductibles. They cheered harder.

Healthcare is the top issue cited by likely caucus-goers in a state where you can choose Wellmark Blue Cross or Wellmark Blue Cross.

Climate change is the number two issue.

“It is real, and it is underestimated in its speed and severity. Australia, a beautiful country, is on fire,” Sanders thundered as the crowd roared back. “Crop production will decline. Climate refugees are around the world in the millions, leading to more war. And we have a president who denies it all.”

The Smith sisters, Paula and Lou, buried their mother with a Hillary Clinton sticker a few years ago. They fell into the Bernie bandwagon at that rally. Their brother Rob was waffling among Sanders, Buttigieg, Biden and Yang.

Dan Berglund said he probably will be “a banker for Bernie” as he was four years ago, but he will walk into the caucus as a Yang supporter. If Yang is not viable with the necessary 15%, he will bail to Bernie.

Tim Gallagher, who works for Buena Vista University, says he might vote for any one of them, and will decide on caucus day. “A lot can happen in a week,” he said.

Such as: Warren was endorsed by the largest newspaper in Iowa, the Des Moines Register, on Sunday. She danced a jig on hearing the news Saturday night in Muscatine in eastern Iowa, after taking selfies with hundreds. She has an elaborate, well-tuned organization apparatus in all parts of the state that she is banking will deliver for her.

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So does Sanders, obviously. The front rows on Sunday were impressive in their relative diversity: people of color. Young people, old people. Conservative-looking farmers who came out to listen to a democratic socialist.

Sanders said his Berniecrats knocked on an Iowa door every two seconds on Saturday – over 100,000 homes.

“There’s nobody in the state with a stronger grassroots volunteer movement,” Sanders said. “Our agenda speaks to the questions and pain that people have in their lives […] I’ve talked to too many people in Iowa who are making 10 to 12 bucks an hour.”

He lit them up again.

That’s what this caucus cycle is about. Sanders has tapped into a vein of frustration that elected Trump, and is getting people of all stripes to give him a look. Pundits’ warnings about a Sanders “ceiling” have begun to sound like the products of people who fear his potential strength.

• Art Cullen is the editor of the Storm Lake Times in north-west Iowa, where he won the Pulitzer prize for editorial writing. He is a columnist for Guardian US and is author of the book Storm Lake: Change, Resilience, and Hope in America’s Heartland, out this month in paperback