(Evan Vucci/Associated Press)

Last week, Donald Trump began telling his supporters, in both media appearances and stump speeches, that not only are polls that show him trailing being manipulated (after all, how could any honest poll not show him winning?) but also the election itself is going to be “rigged,” so that his victory will be stolen from him by the powers that be. This idea is ludicrous for a number of reasons, and it’s dangerous because of the delegitimizing effect it could have on the system and the eventual possible presidency of Hillary Clinton. But how far is this idea going to spread? Is Trump going to get help from conservatives in the media? Is he going to convince his supporters that the election is being stolen?

Yesterday, CNN’s Brian Stelter, host of “Reliable Sources,” went after Sean Hannity for helping Trump spread the notion that the election will be rigged, and Hannity — who has been the most enthusiastic Trump supporter in major media — will no doubt fire back during his radio and television shows today. But for the idea to really take hold beyond the kind of core Trump supporters who would nod their heads in agreement if Trump told them that America Ferrera and Aziz Ansari were leading a conspiracy to rob white people of their precious bodily fluids, it needs a kind of widespread validation that it may not be able to get.

Before I explain why, let’s be clear that it would be perfectly legitimate for Trump to express concerns about the way elections are conducted and to advocate for vigilance in matters such as the vulnerability of voting records to hacking. Our election system is archaic in many ways, and its decentralized character — with responsibility for administering elections spread out over thousands of states, counties and cities — is absurdly inefficient. But Trump isn’t trying to offer a coherent (let alone plausible) account of how the election might be stolen from him. He’s just trying to sow fear. It’s of a piece with the rest of his picture of America — a place of chaos, incompetence, misery and despair, where nothing works and nobody wins.

And we should be clear that there’s a difference between fraud, which suggests that somebody is trying to manipulate the results from the outside, and saying the system is “rigged,” which suggests that the system has been set up from the inside to guarantee that one person will win. Fraud does happen, on a small scale and seldom with any possibility of swinging the results of an election (and voter impersonation, the kind of fraud that Republicans claim to be so desperately concerned about that it’s necessary to enact voter-ID laws that disenfranchise thousands, is spectacularly rare). But claiming that the system is “rigged” is a far more dramatic charge to make.

Trump talks about both kinds of problems, in his typically scattershot way. He says that unless we have voter-ID laws, people “are going to vote 10 times,” and if he thinks that’s possible, it suggests that he has never actually voted. But he never specifies exactly how the “rigged” system is going to be deployed against him, or who’s in on the conspiracy. And it would have to be quite a conspiracy in order to swing the election against him. For instance, if you look just at the battleground states where the election will be decided, you see an awful lot of Republicans in charge of administering the election. For instance, the chief election official in Ohio, Jon Husted, is a Republican. So is Ken Detzner, the secretary of state in Florida. So is Paul Pate, the secretary of state in Iowa. So is Barbara Cegavske, the secretary of state in Nevada. I could go on, but does Trump think all these Republicans overseeing elections in key states are in cahoots to elect Hillary Clinton?

The idea is so asinine that even the most partisan Republican would have trouble arguing with a straight face that it’s actually going to happen. That won’t stop Hannity, who long ago proved himself to be reliably mindless on any and every issue, never pretending to possess even an iota of independent thought. And he may get some support from elsewhere on Fox News. Don’t forget that this is a network that spent years flogging the story of the New Black Panther Party’s supposedly epic voter intimidation efforts in 2008, which literally consisted of a couple of guys standing outside one polling place in a heavily African American neighborhood in Philadelphia glowering at people as they went in (and by the way, nobody spent more time pretending to be outraged about that offense against democracy than Megyn Kelly).

But beyond that, and some other fringe sources such as conspiracy-monger Alex Jones, Trump may find it difficult to get support for his charge of a rigged election, even from some media figures you might expect to back him up. Rush Limbaugh, for instance, responded to Trump’s charge by criticizing him for sounding like a sore loser before he had even lost. “I don’t know if he’s trying to arouse sympathy here,” Limbaugh said last week. “All I know is that that doesn’t work. Nobody ever got elected anything ’cause somebody felt sorry for the way they’ve been treated or what have you.”

And this points up a larger difficulty that Trump faces in getting his message amplified the way an ordinary candidate does. In most circumstances, when a presidential candidate comes out with a new policy or a new argument about a controversial issue, in short order the candidate gets support from nearly everyone on his or her side. Other politicians, pundits, opinion writers, radio and television hosts — all will say whenever they have the opportunity that the candidate is right about this, which sends a signal to voters about what they ought to believe and why. But since Trump has divided his own party, he can’t rely on that amen chorus to back him up and help unite Republicans behind him. Sometimes they will, and sometimes they won’t; it will depend on what he’s saying. If he says Hillary Clinton is a crook or we should cut taxes, they’re right with him. But if he says — in August, and with zero evidence to back up the claim — that the election is rigged against him, they probably won’t be.

Trump himself has the biggest megaphone of all, of course, and Republican voters may already be primed to believe that the fix is in (after the 2012 election, 49 percent of Republicans told pollsters that ACORN had stolen the election for President Obama, which would have been quite a feat since the organization had gone out of business some time before). But with only limited validation from his allies and widespread scorn from anyone examining the question objectively, there’s only so far Trump can get with his claim that the system is rigged. Not that this will stop him from saying it — the cheers of the faithful at his rallies will be all he needs to convince himself that he’s on to something.