Susan Page and Fernanda Crescente

USA TODAY

WASHINGTON — Democratic presidential nominee Hillary Clinton is consolidating the support of the Millennials who fueled Bernie Sanders' challenge during the primaries, a new USA TODAY/Rock the Vote Poll finds, as Republican Donald Trump heads toward the worst showing among younger voters in modern American history.

The survey shows Clinton trouncing Trump 56%-20% among those under 35, though she has failed so far to generate the levels of enthusiasm Sanders did — and the high turn-out that can signal — among Millennials.

"I get worried about the bigoted element of our country, and that they will stick with Trump regardless of his stupidity," says Elizabeth Krueger, 31, an actress in New York City who was among those surveyed. She supports Clinton. "She is not going to be a perfect president, but who would be?"

The findings have implications for politics long past the November election. If the trend continues, the Democratic Party will have scored double-digit victories among younger voters in three consecutive elections, the first time that has happened since such data became readily available in 1952. That could shape the political affiliations of the largest generation in American history for years to follow.

In the new survey, half of those under 35 say they identify with or lean toward the Democrats; just 20% identify with or lean toward the Republicans. Seventeen percent are independents, and another 12% either identify with another party or don't know.

Trump's weakness among younger voters is unprecedented, lower even than the 32% of the vote that the Gallup Organization calculates Richard Nixon received among 18-to-29-year-old voters in 1972, an era of youthful protests against the Vietnam War.

In 2008 and 2012, overwhelming support among voters under 30 was a crucial part of Barack Obama's winning coalitions. But that doesn't reflect long-held partisan preferences. The Gallup analysis shows that as recently as 2000 younger voters split evenly between Democrat Al Gore and Republican George W. Bush, and the GOP's presidential candidates carried their support by double digits in 1984 and 1988.

Now some younger Republicans, like their elders, are torn between concerns about Trump and support for their party.

"At first I supported Ben Carson, and when he dropped out, I was supporting Ted Cruz, and I wasn't left with much when he left," Serena Potter, 19, of Brownsburg, Ind., a student at Purdue University, said in a follow-up phone interview after being polled. Now, asked whom she supports, she replies, "If there was a gun to my head, I'd say Trump. ... He is better than Hillary."

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The Millennials survey, the third this year, is part of USA TODAY's One Nation initiative, a series of forums across the country on the most important issues of 2016. The online poll of 1,539 adults age 18-34 was taken by Ipsos Public Affairs from Aug. 5-10. It has a credibility interval, akin to the margin of error, of 4.6.

Census Bureau data released in April estimated the number of Millennials in the United States at 75.4 million, surpassing the 74.9 million members of the aging Baby Boom generation, now 51-69.

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Poll shows that Millennials would flock to Clinton against Trump

WILL THEY VOTE?

Clinton faced her own challenges with winning Millennials' support. During the Democratic primaries, surveys of voters as they left polling places showed Sanders preferred by voters under 30 by an yawning 71%-28%.

Now, she has succeeded in winning over most of his supporters. In the new poll, she is backed by 72% of those who say they had supported Sanders. Eleven percent support Trump and another 11% say they won't vote. Six percent don't know.

However, enthusiasm about the election has ebbed since the survey was taken in March, when Sanders was still a candidate. The percentage seen as most likely to vote has dipped to 72% from 76%, and those seen as not very likely to vote has ticked up to 9% from 7%.

"I started out as a Bernie supporter, but when he dropped out I switched to Clinton," says Will Barkalow, 24, of Nobleboro, Maine, saying he saw "no other legitimate choice." Barkalow, who is starting a tech-repair business, says he is now enthusiastic about supporting her: "She is very good on policy. She is very bad at giving speeches and interacting with people."

Despite her groundbreaking status as the first female presidential nominee of a major party, Clinton does a bit better among young men (58%-22%) than she does among young women (53%-17%). Women are somewhat more likely to say they won't vote for either, 17% compared with 13% for men.

Interestingly, young men are more likely to say sexism is a major reason for hostility toward Clinton: 42% of men compared to 37% of women. Women are a bit more likely to say sexism plays no role at all, 30% compared with 28%.

"A lot of the complaints that I have heard against her is that she is too shrill and not attractive," says Taylor White, 21, of Wilmington, N.C. She studies social work at the University of North Carolina at Wilmington. "When people call women shrill, it is to devalue what they have to say because they are not saying it in a way that makes men comfortable."

Jacob Vander Feer, 25, who works at a big-box store in Bozeman, Montana, calls sexism no more than a minor factor for Clinton. "We have female Supreme Court judges, female senators, females in the House of Representatives," he says. "It is more used as a stance that, if you don't support Hillary, you are a sexist."

Is it Trump or Clinton?

CONVENTION CATASTROPHE

The Democratic National Convention provided a modest boost for Clinton among Millennials.

But the Republican National Convention was a catastrophe for Trump.

More than three of four of those surveyed paid at least some attention to the political conventions last month, by watching them on live TV, reading posts on social media such as Twitter and Facebook or streaming speeches on YouTube.

They didn't like what they saw at the GOP conclave in Cleveland. At least 50% of those surveyed say Trump seemed less presidential, less credible and less trustworthy afterwards. By more than 2-1, they say he seemed less human and less accessible. On each of five characteristics, Trump's standing fell.

Clinton, on the other hand, saw modest improvements in her standing after the convention in Philadelphia. By 39%-27%, she seemed more rather than less presidential, by 35%-23% more human. But while 31% say she seemed more trustworthy, an equal 31% say she seemed less trustworthy -- a sign of how stubborn that perception, her biggest personal vulnerability, has proved to be.

"She lies a lot, in my opinion, with the emails and stuff," says Franklin Tan, 18, a high-school senior from Springfield, N.J., who had supported Sanders and now says he doesn't support either candidate. "If you don't believe in her for president, if you don't think she is going to do a good job, then why vote for her?"

One motivation cited by both Clinton and Trump supporters: Keeping the other candidate out of the White House.

A 54% majority of Trump voters say one of the main reasons they are supporting the billionaire businessman is to keep Clinton out of the White House. And 51% of Clinton supporters said one of the main reasons they are supporting the former secretary of State is to keep Trump out of the White House.

That said, even more Clinton supporters, 57%, say they support her because she has "the right experience to lead;" just 22% of Trump supporters say that of him. The second-ranking reason they give for backing Trump is that he is "authentic;" just 20% of Clinton supporters say that of her.

SHOW US THE GREEN

Green Party nominee Jill Stein and Libertarian Gary Johnson, who have targeted appeals to disenchanted Sanders' supporters, show slightly higher levels of support than among the electorate as a whole.

Johnson is backed by 11% and Stein by 4% in the poll when their names are included, narrowing Clinton's enormous edge over Trump by a bit. In the four-way ballot test, Clinton is at 50% and Trump at 18%, a lead of 32 percentage points for her, compared with 36 points in the two-way ballot.

Among voters of all ages, Johnson is supported by 8.3% and Stein by 3%, according to the RealClearPolitics average of recent nationwide polls.

Tim Leazott, 33, an administrative assistant from Byfield, Mass., describes himself as a moderate Republican who supported Ohio Gov. John Kasich during the primaries and now backs Johnson because of his concerns about both Trump and Clinton.

"It is hard to really feel good about voting for either party's candidate," he says. "It is scary that, throughout the whole country, it has come to these two candidates that are going to determine the presidency for the next four years."