Rep. Debbie Wasserman Schultz (Fla.), chairwoman of the Democratic National Committee, said she finds the accusations "disturbing" and said Cain "should step up and go beyond just his flat denials because they stretch credulity."

"As a woman specifically, these allegations are disturbing and very serious, and Herman Cain needs to come clean and be very clear about what happened," Wasserman Schultz said in an interview here. "It's hard to imagine four completely different women, who have no previous connection to each other, would come forward separately, coincidentally. So he needs to come clean. Flat denials don't cut it -- especially when his former employer reached settlements with two of them."