If the economy slides into recession in the next 12 months, Democrats will be handed a ready path to run against President Trump. They’ll blame him for the downturn and point to his trade war with China, an argument supported by many economists.

Trump, in turn, is faulting others for the economy’s hiccups: Federal Reserve Chairman Jerome Powell, “badly run and weak companies” and — why not? — the media.

The president has reason to worry. His latest round of tariffs on imports from China covers far more consumer goods than before. JPMorgan Chase estimates the tariffs could cost an average American family as much as $1,000 a year, enough that many voters will notice.

But let’s imagine a more complicated picture. Let’s say Trump gets a trade deal with China, the tariffs come off, and the economy putters ahead at its current growth rate of about 2% — not a boom, but not bad.

What should the Democrats say then?

First, of course, they have to avoid sounding as if they’re rooting for a recession — not even a tiny one. It’s bad form and bad politics.

Second, they can change the subject. That’s the advice of Lynn Vavreck, a UCLA scholar who wrote a landmark study of how the economy affects presidential campaigns.

“The most challenging thing in a presidential election is to be the party out of power when there’s a strong economy,” Vavreck told me.

In most elections, a robust economy means the incumbent party will win — but not always.

In 1976, Democrat Jimmy Carter defeated President Ford by focusing on ethics and honesty in the wake of Watergate. In 2000, Republican George W. Bush defeated Vice President Al Gore by pledging to “restore honor and dignity to the White House” after the sullied presidency of Bill Clinton. The economy was in good but not great shape both times, a bit like its condition today.

This time, Democrats could run against Trump by focusing on his character and his erratic conduct. And they can talk about issues on which voters don’t approve of the president’s performance: healthcare, immigration, race relations, gun control.

The economy hasn’t been some Democrats’ overriding focus this year. Joe Biden argues he’s best positioned to defeat Trump and “restore the soul of this nation.” Bernie Sanders pledges to lead a “political revolution” and enact “Medicare for all.” Pete Buttigieg, who is 37, says it’s time for a new generation of leadership.

But Democrats shouldn’t avoid talking about the economy. For decades, economic opportunity, financial security and even access to education have become more difficult for most families to achieve. That’s the aching, underlying problem of American politics: building a middle-class life seems harder than before.

All the Democrats have tried to hit those themes. They’ve talked about reversing Trump’s tax cuts to the wealthy, relieving student debt, increasing support for education, and other solutions.

Biden’s approach has been generic and relatively moderate. He says he wants to “restore the middle class,” but he hasn’t added much detail to that.

“When I’m president, we’re going to have a fairer tax code,” he said in Iowa recently. “We’re going to build an economy that doesn’t just reward wealth. We’re going to build an economy that rewards work. We’re going to build an economy that works for everyone.”

Can you name any new policies Biden has proposed? Probably not — because that’s not what his candidacy is about. It’s about restoring the normalcy of the era he calls the “Obama-Biden administration.”

Sanders, by contrast, has recycled his sweeping proposals from 2016: Medicare for all, free college for all, a federal job guarantee for every working-age American — and a political revolution to make it all happen. In short, democratic socialism.

“We will no longer tolerate the greed of Wall Street, corporate America and the billionaire class,” he thundered in Iowa. “We will no longer stand idly by and allow three people in this country to own more wealth than the bottom half of America.”

Elizabeth Warren was the surprise candidate of the summer. After months of relentless campaigning, she rose to a virtual tie with Sanders for second place in most polls.

Some ascribed her rise to her wonky refrain of “I have a plan for that.” But I think she’s winning attention because she’s talking about the political economy in big, imaginative ways.

She’s the only nonsocialist with a simple, memorable policy idea: a 2% wealth tax (“2 cents,” she says) on households worth more than $50 million. It may not be workable; it may not even be constitutional. But it has the political virtue of being easy to understand.

And it’s a proposal that encapsulates her larger argument: that decades of deregulation have created an economy that’s lopsided.

“When you see a government that works great for the rich and powerful and is not working much for anyone else, that is corruption pure and simple,” she said Monday in New Hampshire.

This Democratic campaign could come down to a race between Biden and Warren: old-school restoration against disruptive reform. If she wins the nomination, Warren’s message on the economy will be one of the factors that pushed her to the top.

McManus’ column appears on Wednesday and Sunday.