For weeks, polls have shown former Godfather’s Pizza CEO Herman Cain holding strong despite the revelation of sexual harassment allegations against him. Now, his support is starting to collapse.

A new CNN poll finds Cain dropping 11 points among Republicans, from 25 percent in October to 14 percent on Monday. That puts him in a statistical tie for third place in the GOP nominating contest with Texas Gov. Rick Perry.

New polls suggest that voters are turning on Cain. (Darryl Webb/AP)

“Roughly four in 10 Republicans think this is a serious matter and tend to believe the women who made those charges," CNN Polling Director Keating Holland said.

The likely explanation: Cain supporters were looking for a viable conservative alternative before jumping ship. Polls had shown growing concern over the allegations for weeks, even as the Republican’s overall numbers stayed strong.

Those supporters appear to have settled on former House Speaker Newt Gingrich , who jumped from 8 percent to 22 percent in the CNN poll.

Other polls found Cain slipping, although not as dramatically as in the CNN survey.

A CBS poll three days ago found a seven-point drop in Cain’s support from mid-October, but he still led the field with 18 percent.

Pollsters from WSJ/NBC News went back this weekend to 102 Republicans surveyed in last week’s poll, to see if anything had changed since two women went public with their accusations against Cain (and Perry said “Oops.”)

The number of respondents who said they were concerned “a great deal” or “quite a bit” by the allegations against Cain rose significantly, from 17 to 28 percent.

Overall support for Cain, however, dropped by just one point, from 29 percent to 28 percent. And the 102 Republicans who agreed to be re-surveyed already had a somewhat more negative view of Cain than the total original sample — only 13 percent of all respondents in the original poll said they were “a great deal” or “quite a bit” concerned by the allegations.

Cain’s numbers with women have also been eroding. Cain already relied overwhelmingly on male voters for his support, but his drop in female supporters is now large enough to have an impact. He dropped 13 points with women in the CBS poll since mid-October.

More on Postpolitics

Sharon Bialek’s ex-boyfriend speaks

Gloria Cain speaks about harassment

Cain jokes about Anita Hill