The poll showed the percentage of Republicans who view Cain favorably dropped 9 percentage points, to 57 percent from 66 percent a week ago…

A majority of respondents, 53 percent, believe sexual harassment allegations against Cain are true despite his denials. Republicans were less likely to believe they are true, with 39 percent thinking they are accurate.

“The most striking thing is that Herman Cain is actually seeing a fairly substantial decline in favorability ratings toward him particularly among Republicans,” said Ipsos pollster Chris Jackson…

Four in 10 respondents said this issue had made them less favorable toward Cain. About one in three Republicans, or 35 percent, said the controversy had made them less favorable toward Cain.