Updated

Which of the two current front-runners for the Republican nomination is a “true conservative?” By a 13 percentage-point margin, more American voters say Newt Gingrich (53 percent) than Mitt Romney (40 percent). Among self-identified conservatives, the difference widens. Gingrich has a 19-point advantage over Romney when it comes to the “true conservative” trait among this group.

That’s according to a new Fox News poll that asked voters whether a variety of traits described the top GOP contenders -- and Barack Obama.

Click here for full poll results.

There is widespread agreement that each of the three candidates is “smart,” with slightly more voters saying that applies to Obama (81 percent), than Gingrich (77 percent) or Romney (76 percent).

Majorities say the word “phony” does not apply to any of them.

“Strong leader” is not a trait that most voters see in Obama, Romney or Gingrich. The poll, released Thursday, shows that 50 percent think Gingrich is a strong leader and 49 percent think the same of Romney. Some 46 percent of voters think Obama is a strong leader, while a 52 percent majority disagrees.

In addition to leadership and intelligence, empathy is a trait many voters want in their president. Nearly seven voters in 10 think the word “caring” describes Obama (68 percent) and more than six in 10 agree it applies to Romney (62 percent). Just over four in 10 see Gingrich that way (44 percent).

By double-digit margins, more voters think Romney (75 percent) and Gingrich (71 percent) are patriotic than think the same of Obama (60 percent).

Majorities say “presidential” describes Obama (57 percent) and Romney (53 percent), while 43 percent think that word describes Gingrich.

Likewise, many more voters see Obama (57 percent) and Romney (54 percent) as “honest” than think that describes Gingrich (40 percent).

Romney’s best traits are “smart” and “patriotic,” and his worst are “true conservative” and “strong leader.” Gingrich does best on “smart” and “patriotic,” and worst on “presidential” and “honest.”

Obama does best on “smart” and “caring,” and worst on “strong leader” and “presidential.”

The Fox News poll is based on landline and cell phone interviews with 911 randomly chosen registered voters nationwide and was conducted under the joint direction of Anderson Robbins Research (D) and Shaw & Company Research (R) from December 5 to December 7. For the total sample, it has a margin of sampling error of plus or minus 3 percentage points.