WASHINGTON (MarketWatch) — The presidential candidates are promising a lot of cool stuff to the voters — free health care, faster economic growth, a better wall, bigger tax cuts — but the experts who know math say the promises don’t add up.

But what the experts ignore is that many voters don’t really care if the promises add up or not. We don’t care that Bernie Sanders’ universal health care could cost $14 trillion more than advertised, or that Marco Rubio’s tax cuts could increase the deficit by $8.2 trillion, or that Donald Trump’s impenetrable wall around America couldn’t be built for any price.

If voters ever cared about the details of campaign promises, we certainly don’t now. This year, more than ever, we don’t care if the candidates know how to add. This year, we want a president who has a vision for America, a vision of peace, security, prosperity and unlimited hopes for a better tomorrow.

The once-great American middle class is scared to death that our best days are long gone, even though the economy has officially recovered from the recession. We know that millions of people have found work in the past six years, and that the unemployment rate is now below 5%, but we still don’t feel satisfied.

We know that, even in “good” times like these, wages are barely keeping up with the cost of living, especially for essentials like housing, health care and college tuition. No one feels secure. Any of us could lose our job, our home, or our retirement savings in the blink of an eye.

And so we seek candidates who have a clearly articulated vision that gives us hope. The nuts-and-bolts details of how we’ll get there aren’t as important as the vision itself. We want a Moses, a visionary who saw the promised land. Never mind that Moses never got his people there.

Donald Trump has a simple message for voters: He’ll make America great again. KENA BETANCUR/AFP/Getty Images

It’s not surprising that the candidates who have created the most excitement in this campaign season — Donald Trump, Bernie Sanders and Ted Cruz — are precisely the ones with the most clearly defined visions.

Of course, this is Hillary Clinton’s biggest problem as a candidate: her inability to articulate what President George H.W. Bush once dismissed as “the vision thing.”

Clinton’s campaign is all about the nuts and bolts. Name any issue and she has a 20-point road map. She attacks Sanders on the practicalities of his plans, but not his vision.

But she hasn’t been able to explain where she wants us to go. If she had a vision of America — and could really sell it to the voters — she’d probably waltz into the White House. But she’s not giving us what we crave, and that’s why she’s having a hard time beating Sanders, and it’s why she couldn’t beat Obama eight years ago.

It’s no surprise that the two candidates who have most tapped into middle-class anxiety — Trump and Sanders — have put their vision front and center in their campaigns.

For Trump, it’s his ubiquitous slogan: “Make America Great Again.” Trump’s vision is inherently backwards looking.

Appealing to his core constituency of older, blue-collar white men, Trump wants us to imagine that he’ll return America to a Golden Age when men (especially white American men) ran everything, just as God intended, the Golden Age before women and blacks and Latinos and Muslims and gays and immigrants got uppity.

But how will Trump make America great again? Aside from his plans to build his wall against Mexico, deport 11 million immigrants and be a tough negotiator with China, he won’t say. Details are for losers. You’ll just have to trust him, and millions of voters do.

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Bernie Sanders also has a strong vision of an America, one that harkens back to the New Deal and the Great Society but also looks to a progressive future. His campaign slogan promises a “Future to Believe In.” It’s a vision that is resonating with lots of young people who share his belief that the economy and our political systems are rigged against regular people.

Sanders has provided plenty of specifics about how he’d replace our expensive health-insurance system with what he calls Medicare for All, and subsidize college tuition, and raise taxes on the very wealthy, and break up the banks.

But it’s not the details of these plans that has his supporters feeling the Bern, as they say, but his vision of an America of, by and for the people, and not of, by and for the billionaires. It’s the idea of a political revolution that excites them, not the fine print in his plans.

Not every voter is indifferent to the details of what our candidates propose to do, of course. We want to be able to actually solve problems, and to do that we have to have practical and realistic plans. They have to add up. But many of us want more than that in this election.

The big question for the voters is whose vision do you like: Trump’s trek back to a racist and sexist past, Ted Cruz’s reverie of a Christian Caliphate, Sanders’ dream of a progressive future, or some other inspiration that might yet come from Clinton or the Republicans who’ve been left in the dust?

It’s clear to me that the next president is going to have to offer a big, bold vision for the future that addresses the anxieties of the middle class.