Republican presidential candidate Donald Trump speaks in Bangor, Maine, on Saturday. (Photo by Sarah Rice/Getty Images)

Donald Trump's apocalyptic late-campaign rhetoric — the election is rigged, the votes are fraudulent, and everyone's in on it — have a lot of observers concerned. Citing his threat to jail his opponent and his unsubstantiated claims about "rigged" elections, The Washington Post editorial board wrote Monday that "Trump poses an unprecedented threat to the peaceful transition of power."

Trump's October antics may be unprecedented, but his wild allegations about the integrity of the elections might not be having much effect on voter attitudes.

For proof of this, take a look at the chart below, which plots voters' confidence in election results three weeks ahead of the 2012 and 2016 general elections.

The results come from two different surveys — one conducted in 2012 and the other in 2016 — with similarly worded questions posed to nationally representative samples of adults. They show that, among all voters, confidence that their own votes will be counted correctly is essentially flat compared with 2012. Confidence that votes nationwide will be accurately counted is actually up.

Most strikingly, the numbers show that Trump's bombastic rhetoric wasn't having much effect on Republican voters' attitudes as of last week. GOP voters' confidence in the integrity of their own votes dropped just one point, while GOP confidence in the accuracy of other people's votes increased slightly.

A political scientist at MIT, Charles Stewart III, who writes on election-related issues at Cal Tech's Election Updates blog, dug up the 2012 numbers this week. Stewart and his colleague Paul Gronke included a couple questions on election confidence in the 2012 Cooperative Congressional Election Study, which is administered in the fall of election years.

Stewart recently noticed that the questions he asked were similar to questions in a recent Morning Consult survey released this week. While the wording of the Stewart/Gronke question and the Morning Consult question weren't identical, they were close enough that Stewart was able to make some broad comparisons. The results of that undertaking are charted above.

"The most important similarity," Stewart writes, "is that respondents in both 2012 and 2016 were more confident their own votes would be counted accurately than votes nationwide." In 2016, for instance, 45 percent of registered voters are "very confident" that their own votes will be counted accurately. Confidence in the accuracy of vote-counting nationwide falls to 28 percent among that same group.

But Republican and Democratic opinions have diverged since 2012.

"At the local level," Stewart writes, "Republicans remain about as confident as they were in 2012, but Democratic confidence has grown."

There's a similar pattern in confidence about national vote counting: Democratic confidence has shot way up since 2012. Republicans are up slightly too, although Stewart says the difference is small enough to simply be a methodological blip attributable to the slightly different question wordings.

The net result, at both the local and national levels, is that the confidence gap between Democrats and Republicans has grown significantly. But that appears to be due almost exclusively to Democrats becoming more confident in election results, rather than Republicans becoming more pessimistic.

It's tough to say what, exactly, is driving that big change in Democratic opinion. Stewart thinks it may be a backlash against Trump.

"Trump’s charges appear to have counter-mobilized Democratic opinion in novel ways," he concludes. "Democrats have come to the defense of vote counting, not only in their own back yards, but even in other people’s back yards."

Whatever the causes, this should come as welcome news for observers worried about the possibility of election-related unrest from disaffected Trump supporters on or around Election Day. The polling from 2012 and 2016 suggest that Republicans have about as much faith in the system as they always did, Trump's explosive rhetoric notwithstanding.

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