Washington CNN  — 

With the ranks of declared 2016 presidential candidates growing, a new CNN/ORC poll finds the contests for the Democratic and Republican presidential nominations solidifying around two key points: Hillary Clinton dominates everyone on the Democratic side, while no one has broken out of the pack on the Republican side.

The recent formal entries into the Republican race by Marco Rubio, Rand Paul and Ted Cruz have stirred up the GOP field somewhat, but still, no clear leader has emerged. The new poll finds Jeb Bush has held on to the top spot among Republicans and Republican-leaning independents, but Bush’s edge is slight and there are multiple contenders for the nomination who could overtake him with just a small increase in support at the same time that some previously strong contenders have faded.

Overall, 17% of Republicans and Republican-leaning independents back Bush for the GOP nomination, while 12% support Wisconsin Gov. Scott Walker. Paul and Rubio stand at 11% each, with former Arkansas Gov. Mike Huckabee at 9% and Cruz at 7%. Former neurosurgeon Ben Carson and New Jersey Gov. Chris Christie, both of whom placed second in CNN/ORC polls as recently as last fall, are now well behind the leader at 4% each.

Bush’s edge in the nomination contest extends across several attributes viewed as key to winning the presidency. He is most often named as the candidate with the right experience to be president (27%), as the one with the best chance of beating the Democratic nominee in the general election next November (26%) and as the strongest leader in the large field of GOP contenders (21%). He is also more often seen as the candidate with the clearest vision for the country’s future (19%), who cares the most about people like you (18%), and who most closely shares your values (19%).

On one metric, however, Bush has an emerging challenger. While 18% see Bush as the candidate who best represents the future of the Republican Party, the same share say fellow Floridian Rubio is the best representation of the GOP’s future. Paul, at 10%, is the only other candidate in double digits on this question.

The poll suggests Rubio’s campaign rollout has helped raise his profile in the party, boosting him into the top five in the overall race for the GOP nomination. But sustaining that momentum through the many campaign rollouts to come could be a challenge.

Cruz’s announcement raised his numbers among Tea Party backers, but he has shown little improvement elsewhere. Among tea party supporters, Cruz and Walker tie for the top slot at 15%, Rubio follows at 14%, Paul 12%, and Bush 11% with the rest in single digits. In a March CNN/ORC poll, Cruz had just 6% among Tea Party backers, Walker had 22%.

Cruz and Walker’s tea party strength seems to rest on their credentials as strong leaders, perhaps burnished by their high-profile stands on Obama’s health care overhaul in the Senate and labor issues in Wisconsin, respectively: 21% of tea party Republicans call Cruz the strongest leader in the field, 16% say Walker is.

The poll finds little sign of an announcement bump for Paul.

In general, Republicans see Bush as the best possible candidate to match up against the Democratic nominee in 2016, but in hypothetical general election matchups against Clinton, Bush trails by a large margin, as do each of the other seven Republicans tested.

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Marco Rubio fares best against the former first lady, trailing Clinton by 14 points, 55% to 41%. Bush trails Clinton by 17 points, 56% to 39%. Christie and Paul fall 19 points behind Clinton, each putting up 39% to Clinton’s 58%. Huckabee, Walker, Carson and Cruz each trail Clinton by more than 20 points.

Clinton declared her candidacy for the Democratic nomination for president with a web video and promptly hit the road to Iowa and New Hampshire. Her campaign begins in an extremely strong position among Democrats nationwide: nearly 7 in 10 Democrats and Democratic-leaning independents support her. Overall, 69% back the former secretary of state over Vice President Joe Biden (11%), Vermont Senator Bernie Sanders (5%), former Virginia senator Jim Webb (3%), former Rhode Island governor Lincoln Chafee (1%) and former Maryland governor Martin O’Malley (1%). Clinton is also the second choice of just over half of the Democrats who prefer someone else for the nomination. All told, Clinton is the first or second choice of 83% of the potential Democratic electorate.

Any possible Democratic competitors face a steep uphill battle in trying to draw support away from Clinton. Democrats are broadly enthusiastic about a Clinton candidacy, far more than they are for any other potential nominee. Overall, 58% of Democrats say they would be enthusiastic if she won the party’s nomination. About a quarter say they would be enthusiastic about a Biden nomination (26%) while 11% say so about Sanders, 7% Webb, 6% O’Malley and 2% Chafee.

One area where Clinton’s numbers wilt: Only about half of Democratic men (49%) say they would be enthusiastic about having Clinton atop the Democratic ticket, compared with nearly two-thirds of Democratic women (65%).

Democrats overwhelmingly see Clinton as holding several presidential characteristics. Nearly 9 in 10 Democrats see Clinton as a strong and decisive leader (88% say that description applies to her) and as having a vision for the country’s future (88%). About 8 in 10 say she represents the future of the Democratic Party (82%) and cares about people like them (82%). Democrats are slightly less apt to say Clinton is honest and trustworthy, though three-quarters do view her as honest (75%, about the same as in March).

The CNN/ORC International poll was conducted by telephone, April 16-19, among a random national sample of 1,018 adult Americans. Results for the full poll have a margin of sampling error of plus or minus 3 percentage points. Among the 435 Republicans and independents who lean Republican, it is 4.5 points, and among the 458 Democrats and independents who lean Democratic, it is 4.5 points.

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