11/08/2011 04:32 pm ET Updated Jan 08, 2012

Herman Cain's Ratings Drop, But He Still Ties For GOP Primary Lead

In the wake of sexual harassment allegations against Republican presidential candidate Herman Cain, a new poll released Tuesday by Gallup finds that Cain's lustre may be dimming among Republican primary voters. Cain's ratings still outstrip any other candidate in the pack, though, and he has yet to see a measurable drop in his support in GOP primary polls.

The new Gallup poll, conducted Oct. 24 through Nov. 6 among aopproximately 1,500 national Republicans and Republican-leaning independents, found that Cain's "Positive Intensity Score" has dropped from a high of 34 percent at its peak in early October to 25 percent now. Gallup's Positive Intensity Score is calculated by taking the difference between the percentage of Republicans who have a strongly favorable opinion of each candidate and those who have a strongly unfavorable opinion. In a two-week Gallup survey that only overlapped by one day with the allegations, released one week ago, Cain's Positive Intensity Score was 29 percent.

The Tuesday Gallup release notes that while the new survey includes interviews conducted in the seven days before the allegations were first reported by Politico, Cain's Positive Intensity Score was at an even lower 20 percent in the week after the story broke.

Gallup also notes that Cain's overall favorable rating dropped from 79 percent in the interviews conducted before the allegations broke, to 73 percent after. Cain's favorable rating in the survey as a whole was 76 percent, unchanged from the previous week's release (each week's release overlaps by one week with the preceding and subsequent releases).

All of the new survey's interviews were conducted before Cain's latest accuser, Sharon Bialek, came forward and spoke to the media on Monday.

Any drop in the intensity of favorable opinion for Cain has yet to show up in horserace polls of the Republican primary. Two surveys released Monday, one by Gallup and one by NBC News and the Wall Street Journal found Cain and Mitt Romney tied for the lead in the nomination contest. Both the polls were conducted entirely in the days since the original allegations against Cain were reported by Politico. Neither one showed a drop in Cain's support from the previous surveys by the same pollsters. And despite the fall in Cain's Positive Intensity Score, he remains 11 points ahead of his closest opponent on that measure in Gallup's polling, Newt Gingrich.

A Pew survey released Monday found that 29 percent of Republicans believe that the allegations made against Cain are true, while 39 percent believe they are false. The new NBC News/Wall Street Journal poll also suggests that the allegations' effect on the likelihood of Republican primary voters to vote for him might be limited. Among registered voters who said they would vote in a Republican primary, 13 percent expressed "a great deal" or "quite a bit" of concern about voting for Cain based on the allegations, while 69 percent said they had either "just a little" concern or "none at all."

Although Cain joked Tuesday that his name recognition had likely skyrocketed as a result of the allegations, Gallup's polling finds that is not the case, at least among the potential pool of Republican primary voters. Eighty-one percent of Republicans in their new release recognize Cain, compared to 78 percent two weeks ago.

Although the intensity of feelings for Cain has dropped since the sexual harassment allegations surfaced, he still has the highest Positive Intensity Score and the highest overall favorable rating among national Republicans of any GOP candidate. Any drop in his rating has yet to materialize in a drop in his support in the primary race. The drop in Cain's ratings in Gallup's polling since the allegations were reported, though, shows that the issue could prove a vulnerability for the candidate as long as it remains in the news.