It’s extraordinary that Chris Wallace had to ask this question of Donald Trump during a presidential debate: If he loses, will he accept the result of the election?

But what is even more stunning was Trump’s response: You’ll just have to wait and see.

“I will look at it at the time,” Trump said. He listed off his litany of complaints about the election. The media is biased. There are “millions of people registered to vote that shouldn’t be registered to vote,” he said, distorting a Pew Research Center report that was about voter registration systems rather than fraud. Clinton, he said, shouldn’t even be running in the first place.

Wallace pressed him again: “There is a tradition in this country, in fact one of the prides of this country is the peaceful transition of power, and that no matter how hard-fought a campaign is, that at the end of the campaign that the loser concedes to the winner. Not saying that you're necessarily going to be the loser or the winner. But that the loser concedes to the winner, and that the country comes together in part for the good of the country. Are you saying you're not prepared now to commit to that principle?”

And again, Trump wouldn’t say that he would. “I'll tell you at the time,” he repeated. “I'll keep you in suspense, okay?”

Trump seems to be treating his decision about whether to concede in the presidential election like it’s a decision about whom to fire on his reality TV show The Apprentice. If you want to know what he’s going to do, well, you’re just going to have to sit through the commercial break — or the next 20 days of the election — to find out!

But Trump is playing with fire. Even without prompting from their presidential candidate, a sizable share of the Republican base is primed to think that the results of an election they lose are illegitimate. Nearly one-third of Mitt Romney supporters in 2012, including Trump, thought Romney had actually won the election and President Obama had prevailed through fraud.

Political scientists, meanwhile, have found that people’s perceptions of whether an election is legitimate are easily affected by how their preferred candidate responds — a close election where the loser concedes gracefully is considered as valid as a landslide.

We think the winner of a presidential election gets all the power. But it turns out that the loser can control something even more important: the perception of democratic legitimacy. Rather than treat this responsibility with the gravity it deserves, Trump seems determined to milk it for every last second he can stay in the national spotlight.

Correction: This article initially said that there are only 19 days until Election Day. Unfortunately, there are still 20.

Watch: How presidential debates are won and lost