Donald Trump is an unlikely economic hero for the voters of Iowa.

Other Republican candidates attempt to sound like agricultural experts, pandering to rooms supposedly full of farmers by expressing their undying love of ethanol and their undying hatred of the Environmental Protection Agency.

Trump, in contrast, spent several precious minutes at a recent rally explaining to his loyal fans how you could make a fortune buying and selling parcels of land the government was obtaining through the powers of eminent domain.

It didn’t matter that nobody inside the gym at Muscatine high school (“Home of the Muskies”) was likely to follow his lead. It didn’t even matter that this extended discussion was a rebuke to an attack ad aired by his arch-rival in Iowa, Senator Ted Cruz.

All that mattered, on the economically struggling banks of the Mississippi, was that Trump knows how to make money.

Trump’s biggest applause line is that he is so wealthy that he cannot be bought. His wealth gives him a unique vantage point from which to tear down every other candidate in the field, and to promise to create wealth for the rest of the country.

“I’m spending my own money. I’m not using other people’s money. I’m the only one. I’m the only one. I’m the only one doing that,” he said to cheers and applause, as he mocks Jeb Bush’s profligate spending and Cruz’s oil industry funding.

“I turn down so much money,” he lamented. “I feel so foolish. My whole life, I take. Greedy. I take. I take! Greedy! Greedy! Now I’m going to be greedy for the United States. I’m going to take for the United States. I’m going to be so greedy.”

Forget trickle-down economics: Donald Trump is selling knockdown economics. To thousands of fans across Iowa, his deal-making skills promise something elusive: a better deal after decades of trade deals that have contributed to their own economic decline.

Trump’s statements on Mexicans and Muslims may garner most media attention. But his appeal in Muscatine – as it is across Iowa – is built on a relentless bragging exercise about his own wealth-generating powers.

His stump speech bears no resemblance to that of any other candidate: there is no structure and no rhetorical flourish, no policy proposal and few complete sentences.

Trump’s pitch is instead the rambling monologue of a self-inflating mattress salesman on a long airplane journey to the nomination.

Donald Trump speaks at Muscatine high school. Photograph: Andrew Harnik/AP

He paused halfway through his seminar on eminent domain profiteering to note that the Cruz ad shows a tractor tearing down a house.

“It could be a John Deere, but I think it was a Caterpillar,” he said, before explaining how Komatsu has stolen tractor market share because of Japanese yen devaluation. “Speaking of John Deere, we love John Deere. I buy millions and millions of dollars’ worth of them. Millions!”

Judging from the political pandering, you could be forgiven for thinking that this part of the midwest is nothing but cornfields and hog farms. But within a 100-mile radius of where Trump was campaigning in eastern Iowa, there is a long tradition of manufacturing and heavy industry.

John Deere built his steel plow business in Moline, on the Illinois shore of the Mississippi, almost 170 years ago, relying on the majestic river for water power and supplies of raw materials. His successors expanded into the tractor business by purchasing the maker of the Waterloo Boy tractor, across the river in Iowa. Today Deere employs more than 60,000 people worldwide, of which some 10% are still in the Quad Cities area.

Caterpillar’s headquarters are in nearby Peoria, Illinois, barely 90 minutes’ drive south-east. Along the way you could stop off at Galesburg, once home to the massive Maytag refrigerator plant. That plant ran its last shift in 2004, as a young candidate ran for the US senate seat in Illinois.

Barack Obama talked about the Maytag plant in his breakthrough Democratic convention speech, and he returned to Galesburg just 18 months ago to tout his economic plans. But the damage suffered at this western end of the Rust Belt was already devastating by the time Obama reached Washington. Illinois lost one-third of its manufacturing jobs in the outsourcing stampede of the 2000s, and when the Great Recession began, the region was already reeling.

Maytag shipped its manufacturing to Mexico, and at least some of its former workforce found employment with Deere and Caterpillar. For a few years, as commodity prices spiked, the economy held up. Now Caterpillar is undergoing what the company calls “austerity” and John Deere last year laid off more than 900 employees in Iowa and Illinois.

The quality of jobs has gone down. Nobody wants to pay you anything any more James McKillip, former Caterpillar operator

The result is the outsourcing of Iowa’s youth, who seek better jobs and prospects out of state. The sense of decline is pervasive and resonates strongly with Trump’s crowds, as it does with the fervent supporters of Bernie Sanders.

When Trump rails against bad trade deals and Mexican competition, he is talking to the same economic distress as Sanders when his socialist rival rails against corporate America and starvation wages.

Wearing a Caterpillar cap and windbreaker at the Trump rally in Muscatine, James McKillip blames the region’s struggles on the lack of grit among young people and the desperate state of agriculture.

“The quality of jobs has gone down. Nobody wants to pay you anything any more,” said McKillip, who operated a Caterpillar machine for 25 years at a nearby limestone mine. “You can’t get the help. They don’t want to work. People want big bucks but they don’t want to do anything.”

Sanders’ plan to raise the minimum wage to $15 an hour across the country would not work, he said.

“You can’t pay people $15 an hour at McDonald’s. It’s a first job for students to get started. Paying 15 bucks an hour, they’re going to close.”

‘We talked about humility at church today’

Donald Trump attends service at First Presbyterian church in Muscatine, Iowa, on Sunday. Photograph: Andrew Harnik/AP

Humility is a strange concept for Donald Trump. So strange that he was taken aback when, on a rare trip to church in Iowa, the Bible reading was accompanied by a speech on the unfamiliar subject.

Sitting in the fifth row of the red-brick First Presbyterian church in Muscatine, Trump visibly perked up at the reading from I Corinthians 12, and the warning to avoid self-importance that followed.

“What a day. What a day. Just got back from church and it was good. It was really good. I learned something. We talked about humility at church today,” he said an hour later, as he unfolded his rarely used notes at the town’s high school.

“I don’t know if that was aimed at me. Perhaps. Now the church didn’t know I was coming. So maybe it was just by luck. But we talked about humility.”

If the discussion of humility punctured Trump’s consciousness, the effect did not last long. Within minutes, Trump was in full bragging mode.

Whether he talks about his polls or his wealth, his proposition amounts to a Berlusconi-like appeal to voters: my success rubs off on people. According to the candidate, if a TV network features Trump, their ratings go up.

“Meet the Press, Chuck Todd, they were down in the toilet with the ratings,” he explained in Muscatine, before saying that he granted an interview to the moderator of the NBC show, Todd, because he was a nice guy.

“He went through the roof. They had millions of people watching. They all said what happened? He’s going to go in and get a raise now, probably.”

The Trump magic rubs off on even those who trash him. The National Review’s recent cover (“Against Trump”) might now sell a few copies. In contrast, Glenn Beck was a “total loser” who got fired from Fox News and just endorsed Ted Cruz.

“I will be the greatest jobs president that God ever created, believe me. Believe me! Believe me!” Trump said, forgetting again the morning’s lesson about humility. “Trust me. The trade is going to be great. We’re going to bring back jobs. We’re going to make good deals not bad deals. I’m going to use the greatest business people in the world. I know many of them. Most of them. I know the good ones. I know the bad ones. I know the ones that are overrated. I know the people you never heard of.”

All the struggling voters of Iowa need to do now is vote for his gold-plated promise of untold wealth.

“I honestly believe it’s very important because you haven’t had a winner in so long. You are going to have a winner. I give you my word,” Trump said, as his fans started chanting his name for a full minute. “You are going to have a winner. We are going to make our country so good.”

To many voters crushed by decades of economic decline, that sounds pretty attractive.

How bad is the economy in Muscatine? “It sucks,” said Eric Waack, who lives in Wilton, Iowa, and operates a crane at a local steel factory. “There aren’t enough jobs. We need more jobs.”

What will Trump do to help create jobs?

“People need more money to help small businesses,” he said. “Hopefully we’ll get more people with jobs back. It seems like since Obama got in, everybody has been losing jobs and businesses are shutting down.”

As he talked, the Trump rally was winding down to the campaign’s unique soundtrack. First, You Can’t Always Get What You Want by the Rolling Stones. Then, Nessun Dorma, sung by Pavarotti.

Trump’s appeal is that he can always get what he wants, and that maybe you can too if you vote him into the White House. If that doesn’t convince you, maybe you should just vote for a winner. Vincerò!