If Donald Trump's presidential campaign were functional, this would be Economy Week for Team Trump. The presumptive Republican presidential nominee and his surrogates would be wielding the disappointing May jobs report as a cudgel to bash the lackluster "Obama-Clinton" recovery. After all, polls say jobs and the economy remain voters' biggest concern. And it's an issue in which Trump has a big lead over Clinton. A new Gallup poll gives the famed businessman a 10-point edge on "the economy" and a seven-point lead on "employment and jobs."

But Trump isn't talking about the economy. Instead, he's attacking the Mexican heritage of the Trump University lawsuit judge, speculating on the potential bias of Muslim judges, and instructing his surrogates to attack any and all critics as racists.

Trump seems unable to see it, but a lousy economy remains the greatest threat to Clinton's White House hopes, and thus the greatest aid for Trump's presidential bid. The anemic recovery hardly seems a tailwind for Clinton's campaign. A year ago, Yale economist Ray Fair, well known for using the economy to predict elections, said continued sluggish-though-improving GDP growth implied "a fairly large loss for the Democrats."

Since then, the economy hasn't picked up. Fair has noted that the economy, "in terms of the growth rate of GDP, is clearly not a plus for the Democrats in 2016. This could, of course, be trumped by other factors." Ah yes, economist humor. But he's right. Non-economic factors matter, too — like if one major candidate suffers from maniacal narcissism and a proclivity to utter bigoted comments. Millions upon millions of voters may ultimately decide Trump is simply unfit for office even if real disposable income and the labor force participation rate stay steady but meh.

But what if the economy doesn't stay in this same-old, same-old mode? What if is worsens sharply?

That's why Team Clinton should pay close attention to that jobs report, even if Trump isn't. Job growth has slowed sharply, a possible harbinger of deeper economic trouble. Not only did the jobs report show a meager 38,000 net jobs created last month, but totals for March and April were also revised considerably lower. Over the past three months, then, job gains have averaged 116,000 per month. That's about half the average monthly gain since 2010. Barclays recently explained why this is worrisome: Essentially, this sort of molasses-slow job growth signals "that risks of a near- to medium-term recession have risen."

That's essentially the same conclusion from JPMorgan's economic team. JPMorgan's model doesn't look at job growth, but other factors such as the unemployment rate, auto sales, and consumer sentiment. And based on those variables and others, the bank sees a 36 percent chance of a recession within a year, the highest so far during the seven-year-old expansion.

The risk of recession is increasing, Still, it's not exactly likely between now and Election Day.

But here's the thing none of these models factor in: the impact of Trump himself. He could become his very own October Surprise through what I have termed the Trump Doom Loop — the negative feedback effects among markets, politics, and the U.S. economy. The better Trump does in the polls, the more people around the world will worry, and the worse it will be for economic confidence... and thus the better Trump does in the polls.

For instance, in a recent op-ed, former Treasury Secretary Lawrence Summers predicted Trump's tax and trade policies would cause "a protracted recession to begin within 18 months" of his election. If the polls stay close, and if Summers' opinion is widely shared, the Trump Doom Loop could begin. People will worry about the real possibility of President Trump. The economy will tank because of that plummeting confidence and rising uncertainty. And Trump will (falsely, but effectively) point to the tanking economy as a failure of the Democrats.

Desperate voters, already pessimistic about the future, might be willing to gamble on Trump in that case — despite qualms about his character, or lack of it.