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 in New Jersey.

The poll also finds that U.S. Rep. Paul Ryan of Wisconsin, the GOP's vice-presidential nominee in 2012, and Mitt Romney, his running mate at the top of that ticket, are viewed most favorably by Republican voters among a list of party bold-faced names.

Contenders receiving support include Mitt Romney (8 percent); physician and pundit Ben Carson (7 percent); New Jersey Gov. Chris Christie (7 percent); former Florida Gov. Jeb Bush (6 percent); Texas Sen. Ted Cruz (5 percent); Kentucky Sen. Rand Paul (5 percent); former Arkansas Gov. and minister 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).

Unlike many polls, respondents were asked to name their preference without being prompted with a list of options. Less than 1 percent of them chose Ryan, despite his top favorability rating. Thirty-seven percent of Republicans said they had no preference at this point.

"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.

"This could lead to a bruising nominating contest," Murray said, "but 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."

Indeed, a majority of the Republican and GOP-leaning respondents, or 57 percent, say they are at least somewhat willing to overlook their own ideologies in order to back a broadly electable nominee.

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 favorable to 27 percent unfavorable. Tea party supporters view the New Jersey governor negatively – 27 percent favorable, to 46 percent unfavorable.

Results of the Monmouth University Poll are based on telephone interviews with a sample of 399 registered voters who say they are Republican or lean toward the party. The findings are subject to an error margin of plus or minus 4.9 percentage points.