FiveThirtyEight had this graph and the comment. "It looks to me as if Mr. Cain had been on a positive trajectory before, perhaps having moved up to about 28 percent of the Republican vote."
Is that blue trendline reasonable?
Some background information. From Wikipedia, "Cain ran as a Washington
outsider and became a front-runner in the race in the fall of 2011.
However, Cain's support plummeted after several women alleged that he
had engaged in sexual harassment or, in one case, a 13-year extramarital
affair. Cain and his wife unequivocally said the accusations were
false, but Cain, citing the toll the allegations had taken on his family
and his political support, suspended his campaign on December 3, 2011."