Brendan McDermid / Reuters

Arguably the most extraordinary moment of the first debate between Hillary Clinton and Donald Trump came at the very end. “One of you will not win this election,” said the moderator, Lester Holt. “Are you willing to accept the outcome as the will of the voters?”

It was extraordinary that, in one of the world’s oldest democracies, there was suspense over how the presidential aspirants would answer the question. And it was extraordinary that the question was asked in the first place. The moderator was not asking whether the losing candidate would support the winning one—as was asked during the Republican Party’s first presidential debate last year. He was asking whether the losing candidate would acknowledge that he or she had lost, presumably in a free and fair election. “In no US presidential debate, at least in modern times, has that question been asked,” Steve LeVine notes in Quartz.

“I support our democracy,” Clinton responded, and “I certainly will support the outcome of this election.”

Trump initially dodged the question, twice reminding viewers that he would “make America great again.” But eventually, after Holt followed up, Trump offered an answer: “If she wins I will absolutely support her.”

Holt’s question, however, had been whether Trump would recognize the integrity of the election result, not support a victorious Clinton. Trump’s conditional clause—“If she wins”—hung in the air as the debate concluded. If, in November, election officials report a Clinton win but Trump has his doubts, then what?

Shortly after the debate, a reporter helped clarify Trump’s view by repeating Holt’s question to the candidate: Would Trump accept the election’s outcome? “Oh yes, absolutely, I will,” Trump responded.

More than any presidential candidate in recent memory, Trump has questioned the legitimacy of the U.S. electoral process. But he’s now on record agreeing to accept the result of that process. On Monday night, he retreated, at least temporarily, from a position that could have corrosive consequences for democracy in the United States.

For months now, and particularly when he’s struggled in the polls, Trump has argued not only that the U.S. political system is rigged against him and non-Washington/Wall Street elites, but that the vote on Election Day could be too. He’s warned that some people might “vote 10 times” and that he’ll only lose the state of Pennsylvania if Clinton cheats. “Help Me Stop Crooked Hillary From Rigging This Election!” Trump implores on his website, where you can sign up as a “Trump Election Observer.” The Trump campaign has expressed concerns over lax voter-identification laws and the potential hacking of electronic voting machines, but has provided little substantive evidence for why voter fraud, which nowadays is very rare in the United States, might be more widespread this election cycle.

Trump is far from the first presidential candidate to accuse opponents of attempting to mess with the election outcome; in 2008, for example, John McCain claimed that the voter-registration group ACORN was trying to tip the election for Barack Obama by “perpetrating one of the greatest frauds” in American history. But Trump has made the allegation more central to his campaign than many of his predecessors did. Hence why Lester Holt felt the need to ask his question.

And Trump has found an especially receptive audience. A recent Pew Research Center poll of registered voters found that only 11 percent of Trump supporters are “very confident” that votes across the country will be accurately counted on Election Day, compared with 49 percent of Clinton supporters. Thirty-six percent of American voters as a whole doubt that the reported outcome will be accurate. (Americans tend to be more confident that their own vote will be counted accurately, but even here there is significant skepticism among Trump supporters.)


Confidence of American Voters in Accuracy of 2016 Vote

Pew Research Center

Pew also found that confidence in the integrity of the election result has been declining for years among Republican voters.


American Voters Who Are Very Confident Their Vote Will Be Counted Accurately, Over Time

Pew Research Center

This doubt among Republicans about the vote may be a function, in part, of resentment over the Democratic Party controlling the White House for the past eight years. (After the Republicans won the 2004 election, 72 percent of Republican voters told Pew they were very confident in the accuracy of the national vote; when the Republicans lost the 2008 and 2012 elections, those numbers dropped to 29 and 21 percent, respectively.) But it’s also likely symptomatic of growing distrust of government institutions in the United States and many other countries—disillusionment that has swelled amid the uneven recovery from the 2008 financial crisis.

In the United States, we tend to take for granted that in 2000—when the U.S. Supreme Court effectively granted the presidency to George W. Bush, after one of the closest presidential elections in the country’s history—Al Gore went on TV to accept the court’s decision and concede defeat “for the sake of our unity as a people and the strength of our democracy.”

But a similarly close result between Clinton and Trump might turn out differently. Trump, who isn’t exactly comfortable in the role of loser, could conceivably reject a victory by “Crooked Hillary,” even if officials verify that the election wasn’t rigged. And he could then lead a movement to delegitimize the American electoral process and Clinton’s new administration, potentially sparking a political crisis and even violence. In an election already beset by shadowy hacktivists and explosive leaks, it’s also possible that hackers—whether working independently or at the direction of a state like Russia—could tamper with voter-registration records or vulnerable voting machines, validating Trump’s concerns about voter fraud and generating doubt that would be hard to dispel, even if the actual vote tally isn’t significantly affected by the intrusions. Like terrorism, hacking can be massively disruptive even if it doesn’t inflict much direct damage.

Jorge Guajardo, a former Mexican ambassador to China, recently told my colleague James Fallows that Mexico experienced a situation like this during its 2006 presidential election:

In 2006, President Calderon won the presidency with a vote difference of 0.6 percent. Since before the election day, his leading competitor, Andres Manuel Lopez Obrador (known in Mexico as AMLO) had been questioning the validity of the electoral process (even though it was run by an independent agency, approved with unanimous support by all parties, and every voting place had representatives from all major parties).

It was no surprise that AMLO did not concede after his defeat, calling on his followers to engage in civil disobedience, famously saying, “to hell with the institutions.” It was him or bust. His followers did a weeks-long sit-in in Reforma (Mexico City’s major thoroughfare), and his party’s legislators tried to overtake Congress so that Calderon could not be sworn (through complicated maneuvering, Calderon managed to sneak into Congress and be sworn-in as AMLO’s legislators booed).

On Monday, Lester Holt was subtly trying to find out whether such a crisis could occur north of the border.

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