Traditionally, candidates do not complain about an election being rigged until they have actually lost. But 2016 is not a traditional year, and Donald Trump is no traditional candidate.

Allegations of media conspiracy, partisan collusion and Election Day shenanigans have become a staple of Trump's rally speeches and Twitter blasts. In his widely quoted tweet on Sunday, he was characteristically blunt: "The election is absolutely being rigged by the dishonest and distorted media pushing Crooked Hillary — but also at many polling places — SAD."

Doubling down on Monday, Trump tweeted: "Of course there is large scale voter fraud happening on and before election day."

Suggestions of dark doings at the ballot box, hinted at in earlier phases of the campaign, have become a central theme for Trump in October — especially since accusations of sexual assault threatened to overwhelm his campaign. Surrogates such as Rudy Giuliani and Newt Gingrich thumped that tub over the weekend; and after running mate Mike Pence had failed to do so on Sunday on NBC, he turned up in Ohio Monday talking "voter fraud" and recruiting party poll-watchers from the crowd.

The villains in this speculative narrative usually include the media (especially those reporting on women who have accused Trump of sexual assault), the Hillary Clinton campaign and compliant local officials who might allow skulduggery at actual election sites. Trump has also added "global financial interests" to his list of shadowy conspirators "against you, the American people."

That message resonates in some quarters. If you listen to the pollsters these days, most of what they say sounds bad for Trump. But the notion that something is rigged is finding an audience. The idea, and the term itself, were a hit for Bernie Sanders at his rallies earlier this year when he was challenging Clinton for the Democratic nomination. So far, it seems to be working for Trump, as well.

A poll by Politico and Morning Consult done Oct. 13-15 found only 28 percent of registered voters feeling "very confident" their votes would be counted accurately. Among Trump supporters, only 15 percent felt that way. It appears then that, after several weeks of negative stories and adverse developments, the Trump team has decided to change the subject to something the voters respond to.

Some in GOP dissent

As usual, there are other Republican voices with a different hymnbook. House Speaker Paul Ryan has expressed full confidence that "the states will carry out this election with integrity." And Ohio Secretary of State Jon Husted, also a Republican, called out the Trump campaign for its attacks, calling them irresponsible.

In fact, extensive studies by various independent researchers over recent years have found surprisingly few cases of in-person voter fraud. The idea that such infractions could happen on a mass scale according to some master plan ignores the decentralized structure of the American voting system. The Constitution left the administration of elections to the states that, in turn, delegate the job to hundreds and thousands of local authorities, clerks and volunteers.

Nonetheless, the threat of ineligible voters voting (or the eligible voting more than once) remains vivid in Americans' political imagination. It is a reliable source of humor, yes, but also of distrust. There are memories of sketchy vote counts in Chicago in the 1960 presidential election, or in the 1948 Texas Senate race won by future president Lyndon B. Johnson.

More recently, fears of fraud have been stirred by rising numbers of immigrants and visions of noncitizens in voting booths. More than 30 states have moved to tighten their voting requirements in recent years, often prompting pushback from the courts — including, most recently, the U.S. Supreme Court.

Trump himself tends to cast doubt on vote counting only in certain highly specific venues. He has referred to "some precincts" in cities such as "Philadelphia" that "need watching." This follows a longstanding contention in conservative media that voters were intimidated by African-Americans at some urban precincts in the 2008 election.

An article of conservative faith

But what makes the current critique from the Trump campaign more telling for his supporters is its conjunction with a separate indictment — the media. For as long as tales of voter fraud have had currency among conservatives, the notion of liberal media bias has been an article of faith for even longer. The two make a potent combination.

There is an irony here. Trump rose above a large field of rivals in the GOP primaries in large part because he made such a compelling story — especially for cable TV. His rallies and other appearances were often carried in their entirety, while other Republican presidential hopefuls could scarcely get a mention.

Nonetheless, as his prospects have faltered, Trump has increasingly blamed the media. That includes both the news media and the entertainment media, such as the Saturday Night Live episodes that feature a Trump parody by actor Alec Baldwin. Trump sent a Twitter blast against that show hours after it aired over the weekend. The show should be canceled, he said; it's not funny anymore.

But Trump's main antagonists are still the news people. He has been especially at odds with The New York Times, which he is said to read obsessively. He has demanded a retraction for the Times story about two women he allegedly groped in years past. And he has denied categorically all of the alleged assaults that have been detailed in the Times and elsewhere since The Washington Post released an NBC video of Trump himself describing his sexual exploits in offensive language.

Trump can also point to the remarkable array of newspaper editorial boards aligned against him. Even some papers that had never endorsed a Democrat for president, such as the Arizona Republic and the Cincinnati Enquirer, have done so this fall. Several other regular GOP endorsers have opted instead for Libertarian nominee Gary Johnson. No major daily paper has so far backed Trump. USA Today, which has never endorsed anyone for president, published an extraordinary editorial urging readers not to vote for Trump.

Such a phalanx of opposition can be read as an extraordinary critique of the candidate, of course, but for Trump supporters it is obviously an indictment of the media. Frequent surrogate Newt Gingrich has said that without the media ganging up on him, Trump would be ahead of Clinton "by 15 points."

Playing a longer game?

Some believe that Trump is focusing on the media now not to turn around the polls but in hopes of building a movement after the election. If he loses, he will have a following among those who think he was denied the White House unfairly or by media moguls in collusion with the Clinton campaign.

All this folds neatly into another conspiracy theory — one that is popular, you guessed it, with the media. It has Trump reorganizing his post-election empire around a new enterprise, a cable TV network that will either be built from scratch or grafted onto a pre-existing TV operation. Trump's son-in-law Jared Kushner was reported Monday to be talking to potential investors in New York about just such a project.

Some have surmised that Roger Ailes, the political ad-maker and legendary TV producer who invented Fox News in the 1990s, might run the new Trump TV (or "helm" it, as they say in Variety). Ailes is no longer at Fox, having been forced out by lawsuits over his own sexual behavior.

Whether or not Ailes would be interested in a Trump alliance down the road, he has not been prominent in the campaign apparatus to date. That is notable given Ailes' involvement with Richard Nixon and Ronald Reagan — helping make those men winners in a total of four presidential elections.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.