Poll: Trump, Carson dominate GOP field as Fiorina falters

Washington (CNN)Donald Trump and Ben Carson now stand alone at the top of the Republican field, as Carly Fiorina's brief foray into the top tier of candidates seeking the GOP nomination for president appears to have ended, a new CNN/ORC poll finds.

Fiorina has lost 11 points in the last month, declining from 15% support and second place to 4% and a tie for seventh place.
At the same time, Carson has gained eight points and joins Trump as the only two candidates with support above 20%. As in early September before Fiorina's spike in support, Trump and Carson are the first choice candidate of about half of the potential Republican electorate. All told, nearly two-thirds of Republican voters choose Trump or Carson as either their first or second choice for the nomination.
    No other candidates made significant gains since the last CNN/ORC poll conducted just after the Republican debate hosted by CNN and the Ronald Reagan Presidential Library.
    Overall, Trump's 27% leads the field, followed by Carson at 22%, both head and shoulders above their nearest competition. Former Florida Gov. Jeb Bush and Florida Sen. Marco Rubio are tied for third place with 8% support each, followed by former Arkansas Gov. Mike Huckabee and Kentucky Sen. Rand Paul each at 5%. Fiorina, New Jersey Gov. Chris Christie and Texas Sen. Ted Cruz each have 4% support, while Ohio Gov. John Kasich is at 3%. Former Pennsylvania Sen. Rick Santorum stands at 2% and South Carolina Sen. Lindsey Graham holds 1%.
    The new poll comes amid a flurry of polling being released about a week before the GOP candidates will again meet on the debate stage. The polling criteria set by the organizers of that debate, set to take place October 28, appear likely to result in 10 candidates taking the main stage. Aside from Wisconsin Gov. Scott Walker, who ended his campaign shortly after last month's debate, it's likely to be a rematch of those who debated in Simi Valley.
    Fiorina's decline comes across the demographic and political spectrum, with her support now topping out at 8% among those with college degrees. Last month, she stood at 22% among the same group. Fiorina has dropped 11 points among women and 12 points among men, fallen 18 points among independents, 17 points among those age 50 or older, and 15 points among conservatives.
    The poll finds Republican voters increasingly satisfied with their field of choices, 32% say they are "very satisfied" with the group of candidates running for president, up from 23% in July. Republicans also remain more enthusiastic about the presidential race than Democratic voters. In the new poll, 68% of Republican voters say they are extremely or very enthusiastic about voting for president in next year's election, compared with 58% among Democratic voters.
    Those enthusiastic voters are even more strongly behind Trump and Carson than Republican voters generally, while less enthusiastic Republicans are more likely to say they back Bush. Trump's support among the enthusiastic voters is 30%, with Carson at 25%, while Bush's support dips to just 3%. Among those who say they are "somewhat enthusiastic" or less, 22% back Trump, 16% back Carson and 15% back Bush.
    There are some signs in the poll that Carson's numbers get a boost if turnout in GOP primaries and caucuses follows the same patterns it has in the past. Carson runs about evenly with Trump among the groups that make up the largest blocs of GOP primary voters: conservatives, self-identified Republicans and white evangelicals. Carson also nearly matches Trump's support among those voters with college degrees, with 24% backing Trump, 23% backing Carson and 13% backing Rubio.
    A gender gap has reemerged in the data in the last month, with Carson matching Trump's support among women (23% back each) with Bush behind at 9%, Huckabee at 7% and Fiorina and Rubio each at 6% among GOP women.
    Trump has larger edges over Carson among men (31% to 21%, with Rubio at 10%) and independents who lean toward the Republican Party (32% Trump to 19% Carson).
    The CNN/ORC Poll was conducted by telephone October 14-17 among a random national sample of 1,028 adults. Results among the 465 registered voters who say they are Republicans or independents who lean toward the Republican Party have a margin of sampling error of plus or minus 4.5 percentage points.