When Americans are asked to describe Republican presidential candidate Mitt Romney in a single word, the most frequently recalled description is Mormon. For Herman Cain, it is not a word, but numbers -- 9-9-9, the businessman's highly publicized tax reform proposal.

However, according to a new survey by the Pew Research Center for the People and the Press and The Washington post, many Americans are unable to come up with words to describe the top three candidates vying for the GOP nomination -- Romney, Cain and Gov. Rick Perry. When a word did pop into a respondent's head, it wasn't likely to be positive.

The survey, conducted Oct. 13 to Oct. 16 among 1,007 adults, found that almost half of respondents -- 46 percent -- could not offer a one-word description of Cain, who has never held an elected office and is relatively new to the Republican playing field. Meanwhile, 44 percent did not have a word associated with Perry and 37 percent did not have one for Romney.

Party Identification: A Factor in Word Choice

Those who did not identify with the Republican party tended to use neutral or negative words to describe the candidates, while conservatives were more likely to gush  --  except over Perry, when even self-described Republicans and Republican-leaning Independents were more likely to use a negative word (19 percent) than a flattering one (9 percent).

In total, about as many positive (12 percent) as negative (14 percent) words were associated with Cain, who received considerably less negative descriptions than the other candidates. Good, Interesting and Likeable were popular descriptions of the former Godfather's Pizza CEO, along with Business, Inexperience and Pizza. Among respondents who identified as members of the GOP, 22 percent used favorable language for Cain, versus 5 percent who were negative. Cain was the only candidate to receive significantly more positive rather than negative descriptors from his own party.

For Romney, who also ran for the Republican ticket in 2008, 21 percent used negative words -- such as Flip flop, No and Questionable -- while 11 percent associated the former Massachusetts governor with something positive, like Intelligent and Competent. After Mormon, Romney's religious affiliation, the word most popularly connected with the candidate is healthcare. Among Republicans, Romney was met with slightly more positive than negative language -- 18 percent versus 15 percent.

Perry: Much PR Work Needed

The survey indicates that Perry's public relations team has a lot of work ahead of them. While most respondents used Texas, the governor's home-state, to describe him, No and Idiot were also top contenders. Twenty-five percent of respondents used negative language -- such as Dislike, Crook and Scary -- while 6 percent said something positive. The only clearly positive word used among the general respondents, according to Pew, was Strong.

Among the Republican respondents, the negative language against Perry was not as intense. Aside from Texas, he was most often described with Conservative, No and Good.

Perry was considered a frontrunner as recently as early September, but has been steadily losing clout since then. While Gallup reports that Republican support for Perry surged to 31 percent in mid-September, it plummeted to 15 percent by Oct. 7. The most recent poll reports that Romney is the favorite, with 20 percent of GOP support, closely followed by Cain with 18 percent.