At this point, the Republican 2016 presidential field is an undifferentiated mass with none of more than a dozen possibilities garnering over 10 percent support for the nomination, according to a national poll released Tuesday by Monmouth University.

Mitt Romney, the 2012 GOP nominee, stands atop the heap with 8 percent of respondents backing a second try. Gov. Christie, a bona fide celebrity in some circles, drew 7 percent.

"The Republican field is wide open, with different factions of the party circling around very different candidates," said Patrick Murray, director of the Monmouth University Polling Institute in West Long Branch, N.J.

In contrast, Democrats are coalescing around former Secretary of State Hillary Rodham Clinton.

Unlike many polls, respondents were asked to name a preference without being prompted by a list of options.

Other GOP contenders receiving support included physician and pundit Ben Carson (7 percent); former Florida Gov. Jeb Bush (6 percent); Texas Sen. Ted Cruz (5 percent); Kentucky Sen. Rand Paul (5 percent); former Arkansas Gov. Mike Huckabee (3 percent); Wisconsin Gov. Scott Walker (3 percent); Louisiana Gov. Bobby Jindal (2 percent); Texas Gov. Rick Perry (2 percent); Florida Sen. Marco Rubio (2 percent); and former Pennsylvania Sen. Rick Santorum (1 percent).

Thirty-seven percent of Republicans say they have no preference at this point, a situation that could presage a brutal nomination fight.

Yet pollster Murray noted that "most GOP voters say they are at least somewhat willing to put their ideological preferences aside in order to get behind the most electable candidate." According to the survey, 57 percent of Republicans are in that category.

The poll was released as Bush announced he is "actively exploring" a White House run.

He has been an early favorite of the GOP establishment and donor class but likely would face resistance from the conservative base of the party - especially for his moderate stands on immigration and education. For example, he supports the national Common Core standards.

In many ways, Christie occupies the same ground as the former Florida governor; both are popular with establishment money-raisers. Bush is another high-profile contender who gets mixed ratings from Republican voters - 39 percent favorable to 30 percent unfavorable.

Tea party supporters are evenly divided on Bush, 39 percent positive and 38 percent negative, while other Republicans give him a 39 percent favorable to 24 percent unfavorable rating.

Overall, Christie gets a favorable rating from 36 percent of GOP voters and an unfavorable rating from 34 percent. He does better among those who do not align themselves with the tea party wing (41 percent to 27 percent), while he is "upside down" among tea party supporters: 27 percent favorable, 46 percent unfavorable.

The poll of 1,008 adults was conducted by telephone from Dec. 10 to 14, and the results are based on a sample of 399 registered voters who say they are Republican or lean toward the GOP. The sample is subject to a margin of error of plus or minus 4.9 percentage points.

The interviews ended before Christie was shown on national television celebrating with Dallas Cowboys owner Jerry Jones that team's win over the Eagles at Lincoln Financial Field on Sunday night.