While Clinton remains strikingly dominant in the Democratic field, the poll shows that her numbers have dropped significantly across several key indicators since she launched her campaign in April.
A growing number of people say she is not honest and trustworthy (57%, up from 49% in March), less than half feel she cares about people like them (47%, down from 53% last July) and more now feel she does not inspire confidence (50%, up from 42% last March).
In head-to-head match-ups against top Republicans, her margin is tighter than it has been at any point in CNN/ORC's polling on the contest.
On the Republican side, though, no candidate has successfully broken out of the pack.
The group of seven that have come to dominate most polling on the race hold the top of the charts in this poll, Sen. Marco Rubio
and Jeb Bush leading the pack with Mike Huckabee
, Wisconsin Gov. Scott Walker, Sen. Ted Cruz
, Ben Carson and Sen. Rand Paul
all in the hunt.
Much of Clinton's fade is attributable to shifts among independents, but she's also losing some ground among her own partisans. Her support in the Democratic nomination contest has dropped 9 points since April, and though more than 8-in-10 Democrats said they thought she was honest and trustworthy earlier this year; now, just 73% say so.
The new CNN/ORC poll looking at the shape of the race for the presidency in 2016 finds these warning signs for Clinton, alongside some concerns for the Republican Party's best-known contender, Jeb Bush.
Jeb Bush's family ties
Bush's efforts to separate himself from his brother have worked to some extent. Only about half of Americans say Bush is "a lot like his brother."
But most -- 56% -- say his connection to two former presidents would make them less likely to back him for the presidency. Just 27% say that connection would make them more likely to back the former Florida governor.
That's virtually the opposite situation of what his brother faced when George W. Bush made his initial run for the presidency in 1999. Back then, 42% said Bush's connection to his father made them more likely to back him, while only 24% said it was a deterrent.
Bush's family ties are slightly more of a draw for Republicans, but not by much. Among Republicans and Republican-leaning independents, 42% say they're more likely to back Jeb Bush because of his connections, while 38% say they are less likely to vote for him because of that.
No leader emerges in the GOP pack
For the bulk of the GOP field, however, the race for the Republican nomination remains an effort to distinguish themselves from the pack and no one has yet succeeded at that.
Though there has been some shuffling at the top of the GOP order since the last CNN/ORC poll in April, no individual candidate's movement lies outside of the margin of sampling error.
Rubio tops the field with 14%, with Bush near even at 13%. Huckabee and Walker follow at 10% each, with Cruz (8%), Paul (8%) and Carson (7%) all within striking distance of double-digit support.
Paul prompts the largest gender gap on the GOP side, drawing 13% and tying for first among men while garnering just 2% support among women.
The top of the field is similar among conservative Republicans to the overall horse race numbers, but among those who consider themselves tea party supporters, there's a clear leader: Scott Walker with 19% support. His closest competitor is Ted Cruz with 12%.
Overall, about half of Republicans (49%) would like to see the field resolve early, saying it would be best for the party if one strong candidate emerged early as a clear frontrunner. But 46% say they would prefer a longer campaign, with a number of strong contenders competing over the next year.
One possible differentiator emerges: The poll finds a distinct difference in which candidates Republicans view as representing the future rather than the past.
Three-quarters of Republicans describe Marco Rubio (77%) or Scott Walker (75%) as representing the future, nearly 7-in-10 say so about Rand Paul (68%), but Bush (51%) and Christie (51%) are far less likely to be seen as representative of the future.
The growing Democratic field
Democrats are more likely than Republicans to say they would like a competitive primary (53% say that would be best for the party), but their preferences so far don't portend a close contest.
Clinton continues to hold a massive lead in that race, with 60% of Democrats saying she would be their top choice for the nomination. Behind her, 14% would favor Vice President Joe Biden, and 10% prefer Vermont Sen. Bernie Sanders.
Martin O'Malley, the former Maryland governor who announced his candidacy on Saturday, barely registers with 1% support.
Sanders does fare better among liberals than overall, carrying 18% support among that group, but Clinton still notches 61% among the liberals in her party.
Getting closer to the general
In general election match-ups, Clinton now runs about even with Rand Paul, Scott Walker and Marco Rubio, while she continues to top Bush and Ted Cruz by a significant margin.
As noted above, those shifts stem largely from a change among independents, though Republicans appear to be solidifying their support for GOP candidates while Democrats are slightly less certain about Clinton.
One feature of the race that has held even as the numbers shifted: These match-ups prompt enormous gender gaps. According to the poll, the gender gaps remain over 20 points in each of the five match-ups tested, including a whopping 34-point gender gap in Clinton's match-up with Scott Walker.
Her declining support in those general election match-ups, alongside falling favorability ratings and worsening impressions of her, suggests recent news about her actions as secretary of state may have taken a toll.
Though most -- 61% -- think the release of Clinton's emails over the next months from her time as secretary of state will not reveal any previously hidden wrongdoing, the poll also finds 58% are dissatisfied with the way she handled the attack in Benghazi in 2012.
A narrow majority feel the Republican-led congressional hearings on the attack have been handled appropriately, just 41% say the GOP has gone too far with them.
Clinton's family ties to a president are more of a wash than Bush's. While 39% say her marriage to Bill Clinton makes them more likely to vote for her, the same share say it's a turn-off. And most Americans say Clinton is not like her husband at all (54%).
The CNN/ORC Poll was conducted by telephone May 29-31, among a random national sample of 1,025 adults. The margin of sampling error for results among the full sample is plus or minus 3 percentage points. It is 4.5 points for results among the 433 Democrats and Democratic-leaning independents and the 483 Republicans and Republican-leaning independents.