Story highlights

Donald Trump's poll numbers have him competitive in a general election, a new CNN/ORC poll shows

Clinton's race for the Democratic nomination is also tightening, the poll shows

Washington CNN  — 

Since announcing his campaign in late June, Donald Trump has quickly leapt to the top of the Republican field, leading recent polls nationally, in Iowa and in New Hampshire. And now, for the first time in CNN/ORC polling, his gains among the Republican Party have boosted him enough to be competitive in the general election.

CNN Interactive: 2016 election candidates

The poll finds Democratic frontrunner Hillary Clinton ahead of Trump by just 6 points, a dramatic tightening since July. Trump is the one of three Republican candidates who have been matched against Clinton multiple times in CNN/ORC polling to significantly whittle the gap between himself and the Democratic frontrunner. He trailed Clinton by 16 points in a July poll, and narrowed that gap by boosting his standing among Republicans and Republican-leaning independents (from 67% support in July to 79% now), men (from 46% in July to 53% now) and white voters (from 50% to 55%).

But Clinton still holds the cards overall in the race for the White House, leading four Republican contenders: She tops Trump and Wisconsin Gov. Scott Walker by 6 points each among registered voters, former Florida Gov. Jeb Bush by 9 points, and businesswoman Carly Fiorina by 10 points.

READ: The complete CNN/ORC poll

Clinton maintains this edge in the general election race despite a growing perception that by using a personal email account and server while serving as secretary of state she did something wrong. About 56% say so in the new poll, up from 51% in March. About 4-in-10 (39%) now say she did not do anything wrong by using personal email. Among Democrats, the share saying she did not do anything wrong has dipped from 71% in March to 63% now, and just 37% of independents say she did not do wrong by using the personal email system.

And positive impressions of Clinton continue to fade. Among all adults, the new poll finds 44% hold a favorable view of her, 53% an unfavorable one, her most negative favorability rating since March 2001. A majority of women voters have a positive take on Clinton, 52% view her favorably, and her support among women appears to be the foundation for her general election advantages.

But the fading numbers haven’t hurt her against some GOP contenders. Clinton has her biggest lead over Fiorina, topping her 53% to 43% among registered voters. She leads Bush by a nearly identical margin, 52% to 43%. And Clinton tops both Trump (51% to 45%) and Walker (52% to 46%) by 6 points each.

All of those leads are boosted by sizable gender gaps.

Against Bush, Clinton leads 59% to 37% among women, while Bush holds an advantage among men, 51% Bush to 44% Clinton. Against Fiorina, the only woman among the major candidates for the Republican Party’s presidential nominations, women break 60% for Clinton to 39% for Fiorina, while men are about evenly divided, 48% for Fiorina, 46% for Clinton. The largest gender gap – 34 points – comes in a match-up between Clinton and Trump. Women favor Clinton by 23 points, 60% to 37%, while men break in Trump’s favor by 11 points, 53% to 42%.

At the same time, Clinton’s lead in the race for the Democratic nomination for president is narrowing, and the new poll suggests the best way for the former secretary of state to shift the momentum would be for Vice President Joe Biden to decide to sit this one out. Most Democrats, though, say they’d like to see Biden make a run for the White House.

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Overall, 47% of Democratic and Democratic-leaning voters say they support Clinton for the party’s nomination. That’s down 9 points since July, and marks the first time her support has dipped below 50% in national CNN/ORC polling on the race.

At the same time, Vermont Sen. Bernie Sanders has climbed 10 points since July and holds second place in the race with 29%. Biden follows at 14%, former Maryland Gov. Martin O’Malley is at 2%, former Virginia Sen. Jim Webb has 1% and less than 1% back former Rhode Island Gov. Lincoln Chafee.

And though support for Clinton’s nomination bid has slipped, she is the candidate most trusted by Democrats on four top issues, and remains the candidate to beat in general election match-ups.

Should Biden decide not to make a run for the presidency, his supporters would largely flock to Clinton rather than Sanders, boosting her numbers. With Biden’s backers re-allocated to their second choice, Clinton holds 56%, Sanders 33%, with support for O’Malley, Webb and Chafee unchanged.

Among those Democratic voters who are “extremely enthusiastic” about voting for president next year, it’s already essentially a two-person race. Clinton is the choice of 50% of such voters, with Sanders jumping to 38% among that group, Biden at 6%, and O’Malley at 2%.

Still, most Democrats say they do want Biden to make a go of it: 53% of Democrats and Democratic-leaning voters say they think Biden should run, 45% that he should stay out. Even among those who currently support Clinton, 50% say they think Biden should run.

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Democratic voters aren’t necessarily convinced a Biden presidency would be better than a Clinton one, though: 35% say Biden would do a worse job as president than Clinton, 27% a better one and 38% say there wouldn’t be any difference between the two. Those who think Biden should run are more apt to say he’d do a better job than a worse one (41% better vs. 18% worse) but a sizable 41% say there ultimately wouldn’t be any difference between the two.

Fewer see Sanders as equivalent to Clinton, more say he’d do a worse job. Overall, 37% of Democratic voters think Sanders would do a worse job as president than Clinton, 31% that he’d do a better job, and 29% that there would be no difference between the two. That shifts among the party’s liberal voters, 41% of whom think Sanders would do a better job than Clinton, 34% think he would do worse than Clinton and 22% that there would be no difference.

Sanders has boosted his favorability rating in the last month, 35% of adults and 58% of Democratic voters have a positive impression of the senator, that’s up from 23% among adults and 36% among Democratic voters since July.

When Democratic voters are asked which candidate they trust to handle the economy, race relations, foreign policy and the income gap between rich and poor Americans, Clinton tops the list each time. Her biggest advantage comes on foreign policy, where 61% of registered Democrats say they trust Clinton over the rest of the field. Biden follows at 22%, and just 9% say Sanders is their top choice here. On the economy, 45% say Clinton would best handle it, 26% choose Sanders and 21% Biden.