Months after a fractious primary season, California Democratic and independent voters have come home to Hillary Clinton, sharply boosting her popularity and giving her a commanding lead in the nation's most populous state, according to a new USC Dornsife/Los Angeles Times poll.
In late May, just before the state's primary, half of California voters had an unfavorable impression of Clinton, while 47% viewed her favorably. Today, thanks to consolidation of support among Democrats — and substantially improved standing with independents — Clinton is viewed favorably by 56% of California voters, while 42% hold an unfavorable view.
Clinton's improved popularity is particularly notable among groups that heavily supported Sen. Bernie Sanders of Vermont in the primary — young voters and those who are not registered as party members.
In May, voters registered without a party preference were evenly split in their view of Clinton, 49% viewing her favorably and 49% holding unfavorable views. Now, 60% of unaffiliated likely voters hold favorable views of Clinton, while 38% say they see her unfavorably.
Among voters younger than 30, two-thirds now have a favorable view of Clinton, up from just four in 10 on the eve of the primary.
"There's a big improvement since May," said Anna Greenberg, of the Democratic polling firm Greenberg Quinlan Rosner Research, which conducted the survey for The Times and USC along with the Republican firm American Viewpoint.
The unified Democratic support and improved popularity among independent voters have positioned Clinton for a strong showing on Nov. 8. She is supported by 54% of likely voters, the poll found, compared with 30% backing Donald Trump.
Gary Johnson, the Libertarian party nominee, and Green Party candidate Jill Stein are backed by 4% and 3% of likely voters, respectively.
Asked who they would support if they had to choose between the two major-party nominees, 58% of likely voters said Clinton and 32% said Trump. The figures among all registered voters were almost identical to the likely voters.
The numbers indicate Clinton is on track to roughly match the level of support President Obama received in the state in his reelection four years ago, when he took just over 60% of the vote.
Trump, by contrast, may fall below the level achieved by Mitt Romney, the GOP nominee in 2012, who took 37% of the state's vote. The poll found notable weaknesses for Trump among some groups that typically vote Republican, especially married women.
The survey of 1,500 registered voters, including 1,365 considered likely to vote, was conducted by telephone, including landlines and cellphones, in English and Spanish from Oct. 22-30. The results for the likely voter sample have a margin of error of 2.4 percentage points in either direction.
Clinton has always been the prohibitive favorite in reliably blue California, but the grinding Democratic primary battle against Sanders had damaged her standing in the spring.
Ivan Pineda, a 19 year-old student from Santa Ana, was among those who said they had warmed to Clinton since then.
In the spring, Pineda preferred Sanders and his campaign pledge for free tuition at public colleges and universities. Once Clinton clinched the Democratic nomination, however, Pineda had no doubt how he'd cast his vote.
"I've always been on board with the Democratic party," Pineda said.
Heather Lewis, a 32 year-old from Alameda County, said she had briefly considered voting for a third-party candidate after the defeat of Sanders, her choice in the primary.
But, she concluded, "if I were to vote for a third party candidate in this election, I would be voting for Trump, basically. That wasn't really an option for me."
In addition to her own higher popularity, Clinton was also buoyed by Californians' high regard for President Obama, who notched a 64% approval rating among likely voters, the highest level that the poll has recorded since it started in 2010.
Clinton has positioned herself as an extension of Obama's presidency, and Obama on the campaign trail has portrayed his former rival as crucial to upholding his legacy.
The improved popularity has not wiped away all doubts about Clinton, of course. Asked to pick two items that were concerns about her, one in three voters in the state said they were worried she wasn't honest and trustworthy. About three in 10 said they were concerned she had been involved in scandals, and about one in four worried that she was too close to Wall Street.
Predictably, a partisan split colored those views. Republicans were most likely to say that they were concerned about honesty and scandals related to Clinton. Democrats were more likely to cite Wall Street ties.
Asked what concerned them about Trump, about three in 10 voters cited his temperament, another three in 10 cited his lack of experience, one quarter mentioned his style of demeaning people and just under one quarter picked his comments about women and allegations that he had committed sexual assaults.
Clinton leads Trump among most demographic groups in the state, including among white men, a group he dominates in most other parts of the country. In California, white male likely voters sided with Clinton over Trump 48% to 35%, the poll found.
The only major group among whom Trump led was white Californians without a college degree, 44% of whom backed the GOP nominee compared with 39% for Clinton.
Trump remains broadly unpopular with key slices of the electorate, notably Latinos. Among Latino likely voters, 81% viewed him unfavorably, and only 16% said they planned to vote for him.
Among married women, just over half were backing Clinton, and only about one-third planned to vote for Trump.
Mike Madrid, a GOP strategist who was a consultant on the poll, said national Republicans should heed the warnings of California's gender and racial divisions.
"California is a more pronounced example of what's happening demographically in the country," Madrid said.
Republicans are trapping themselves in a "demographic death spiral" by alienating such large swaths of the electorate and relying solely on a shrinking number of white voters, he said.
Greenberg, however, said it remains unclear if the Republican disadvantage among married women was specific to Trump or indicative of a larger, longer-lasting political shift.
"It's Trump's views and behavior" that women voters have reacted to, she said. "I don't know if that extends beyond this election cycle."
The poll also found ominous cracks within the GOP, particularly between those who align with Trump and those who side with party leaders such as House Speaker Paul Ryan of Wisconsin.
Among those voters with a favorable opinion of Trump, only 46% viewed Ryan favorably, while 38% had an unfavorable view of him, the poll found.
Of those who viewed Ryan favorably, only 47% planned to vote for Trump.
"This splintering of the Republican party isn't doing either side any good," said Randall Gutermuth of American Viewpoint.
Colleen Fitzpatrick, a registered Republican from Sacramento, predicted difficult times ahead for her party, regardless of the election outcome.
"The party is going to get split, there's a big divide," she said. "I don't think the party is going to come back together. They may be coming back together to vote him in...but I think we'll end up with a third party."
Fitzpatrick, a 62 year-old retired police officer, was leaning toward voting for Trump, but she still had doubts about his ability to work with Congress.
"I don't think he realizes he's not going to be able to run this country like a business," she said. "He can't go in and say 'you're fired.'"
Barbara Manos, 65, a cosmetics saleswoman and ballet teacher from Contra Costa county, also predicted a GOP split. She said she aligns more with Trump than with the traditional party establishment.
"Possibly if Trump were more politically involved, he might have been able to pull the party together...[but] there are too many career politicians still in there that are going to be contentious," she said.
For all the operatic turns in this presidential race, most Californians developed opinions on the candidates long ago. Among the likely voters who oppose Trump, 77% said they had been against him from the beginning. An even higher share of voters opposed to Clinton, 86%, said they felt that way from the start.
Times staff writer David Lauter in Washington contributed to this report.
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