Susan Page, Jason Lalljee and Jeanine Santucci

USA TODAY

Americans are facing the 2020 presidential election with a dominant feeling: Dread.

A nationwide USA TODAY/Suffolk University Poll found a sharply divided country that views next year’s presidential campaign as a sobering test of the fundamental values of the United States. A majority of those on both sides called the election the most important of their lifetimes.

And after it's over?

If the candidate they support loses, nearly four in 10 said they would have little or no confidence that the election had been conducted in a fair-and-square way, setting up what could be a debate over the legitimacy of the next president. Those expressing doubts crossed partisan lines – 30% of Republicans and 45% of Democrats – although they identified different threats to the electoral process.

In the crowded Democratic contest, former Vice President Joe Biden retained a wide lead, at 32%, up 2 percentage points from the USA TODAY/Suffolk poll taken in June. But Massachusetts Sen. Elizabeth Warren moved up 4 points to second place, at 14%, and Vermont Sen. Bernie Sanders dropped 3 points, now at third place with 12%.

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The sense of towering stakes has been stoked by President Donald Trump, whose sweeping policies and provocative rhetoric has convinced some that he is protecting basic American precepts and others that he is undermining them. If the election were held today, 41% said they would vote for an unnamed Democratic nominee, 39% for Trump. Ten percent said they would vote for a third-party candidate and another 10 percent were undecided.

"Sometimes when you stand up and fight, it's not easy," said Cynthia Lasserre, 81, a Republican from Marrero, Louisiana. "I back him because I feel like he's doing the right thing."

"We have a Constitution, we have a rule of law, (but) President Trump seems to believe, by these tweets, that he can execute laws extra-judiciously, extra-legislatively, as if he were the law onto himself," said John Fortman, 57, an independent from Santa Clarita, California, who was among those polled. "He's a tyrant, or would be if he could get away with that."

The USA TODAY/Suffolk Poll of 1,000 registered voters, taken by landline and cell phone from Aug. 20-25, has a margin of error of plus or minus 3 percentage points.

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More than eight in 10 said they believed that the fundamental values of the United States were being tested in 2020 more so than in previous elections.

Asked to give one word that described how they were feeling about next year's contest, four of the top five responses conveyed alarm and angst, with voters using words such as “frightened,” “train wreck,” “nervous” and “chaotic.”

Elizabeth Warren rises

The Labor Day holiday traditionally marks a new and intensified phase of the campaign. That's especially true for the crowded field of Democratic contenders that may well get smaller before the opening contests are held early next year in Iowa, New Hampshire, Nevada and South Carolina.

Despite some missteps on the campaign trial, Biden maintained a wide edge over his rivals, "The perception that Joe Biden is the likeliest Democratic candidate to defeat President Trump has strengthened his bid across demographics," said David Paleologos, director of the Suffolk University Political Research Center. He likened the standing of Biden, Warren and Sanders to cement that was beginning to harden around the race.

"I like Joe Biden; he's the one I would support," Jonathan Johnson, 52, a lawyer and an independent from Decatur, Georgia, said in a follow-up interview. "The rest of the Democratic Party seems too far to the left of the lane for me."

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Wesley Kinslow, 37, a Democrat from near Memphis, likes the "lofty goals" expressed by Warren. "For a lot of people, they don't see that as a positive," he said, "because they've kind of lost their feeling for what America and being American is, which is having lofty goals and being able to achieve them just through sheer perseverance."

Only three other candidates received support above 2%: South Bend (Indiana) Mayor Pete Buttigieg and California Sen. Kamala Harris, each at 6%, and businessman Andrew Yang at 3%. At 2% were former Texas Congressman Beto O'Rourke and New Jersey Sen. Cory Booker.

Former Housing Secretary Julian Castro and Ohio Rep. Tim Ryan were at 1%. Below 1%, receiving the support of only one or two voters, were Colorado Sen. Michael Bennet, author Marianne Williamson, Hawaii Rep. Tulsi Gabbard and activist Tom Steyer. Steyer was supported by one person, or .24% of those Democratic voters surveyed, below the 2% threshold he needed to be assured a place at the next Democratic debate in two weeks.

The contenders who did not receive the support of a single one of the 424 likely Democratic voters surveyed included Montana Governor Steve Bullock, New York Mayor Bill de Blasio, Maryland Rep. John Delaney, New York Sen. Kirsten Gillibrand, Minnesota Sen. Amy Klobuchar, Miramar (Florida) Mayor Wayne Messam and former Pennsylvania Congressman Joe Sestak.

The sample of 424 registered voters who plan to vote in the Democratic primaries or caucuses has a margin of error of plus or minus 4.96 percentage points. The sample of 289 voters who plan to vote in the Republican contests has an error margin of 5.76 points.

In a field that is still fluid, Warren showed another sign of potential strength. Asked which candidate would be their second choice, 17% picked her, more than any other contender. Buttigieg was the second choice of 12%, Biden and Sanders of 11%.

Paymaan Shafai, 42, a Democrat from Eastvale, California, said there are "three or four that are floating" to the top of his list of candidates, among them Buttigieg, Harris, Sanders, Warren and Booker.

"I'm kind of keeping an open mind," said Shafai, a project manager for a software consulting company. "I think what I like is their demeanors, the way they're able to present themselves and the way they communicate, the way they want to be a little more inclusive."

If their preferred candidate didn't win the presidential nomination, the overwhelming majority of Democratic voters, 81%, said they would vote for the party's candidate. Five percent said they would support a third-party candidate; 4% would vote for Trump, and 3% would skip voting altogether.

Among Republicans, an overwhelming 90% supported Trump; 5% backed challenger Bill Weld, the former governor of Massachusetts. None of Weld's supporters said they would support Trump if he were the GOP nominee, as he is all but certain to be. Half of Weld's supporters would vote for the Democratic candidate, 43% would vote for a third-party candidate, and 7% wouldn't vote. The poll was conducted before former Illinois Rep. Joe Walsh formally entered the race.

Close to half of Republicans said their vote for the House of Representatives or the Senate wouldn't be affected by whether a candidate had criticized Trump. Among those who would be affected, 32% said criticizing the president would make them less likely to support a congressional candidate; 15% said it would them more likely to support him or her.

Among all registered voters, Trump had an approval-disapproval rating of 44%-54%.

Fair and square?

Even the end of the campaign may not be the end of the debate.

Just over half of those surveyed, 53%, said they would be very or somewhat confident that the election had been conducted fairly if their candidate lost. Thirty-eight percent said they would be "not very confident" or "not at all confident" about that.

"I'm not saying I would 100% say, if Trump wouldn't get reelected, that it would be because of voter fraud," said Josiah Reeves, 36, a Republican from Charleston, S.C. "I just definitely think it's a possibility. ...

"Both political parties probably feel that way just with everything going on," he went on. "I know Republicans don't like it, because they think, like, illegals, and things like that are, able to vote. And I know, Democrats think that the whole Russia collusion thing and they interfered. I think everybody's a little on edge about it, and has doubt about it, for sure."

Indeed, the top reason cited by Democrats who lack confidence that the election will be conducted fair-and-square was foreign interference; among Republicans the top reason was voter fraud, with votes being cast by those who aren't eligible. Democrats were more likely to warn of voter suppression, with eligible voters not being allowed to cast ballots.

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A majority of Republicans also said they were concerned about skewed coverage by the mainstream news media and about so-called "fake news," deliberately falsified stories that are created and distributed to distort and confuse readers and viewers.

"I wouldn’t go as far to say it’s been ruined, but I think the American people really do not trust what’s going on," said Lasserre, the Trump supporter from Louisiana. "We worry, I think, is all of this on the up-and-up?"