The official word out of both camps in California is that the decision to cancel their appearance on Ronn Owens’ KGO radio show was “mutual,” though neither would elaborate much more after that.

Whitman has been under scrutiny all week after her former housekeeper Nicky Diaz Santillan alleged Whitman employed her services for nine years knowing she was not in the country legally. Whitman denied the allegations, insisting Santillan provided her with a valid Social Security card and California driver’s license.

The Republican nominee claims she did not know Santillan was undocumented until June 2009, when the housekeeper revealed herself to ask for help getting citizenship. With a tough stance on illegal immigration a part of her platform, Whitman let Santillan go.

Brown’s camp has used the incident go on the offensive. Whitman, however, points out that Santillan’s lawyer is Gloria Allred, who has long been a Democratic activist, and suggests Brown’s people are responsible for Santillan’s story reaching the public.

Tuesday’s debate, announced months ago, was supposed to be moderated by Owens, who is well-known as a tough questioner in the Bay Area. As a call-in show, both candidates could have faced even tougher questions from the general public.

"Ronn Owens is tough - it's a call-in show where they'll get real-people questions," said Barbara O'Connor, a Sacramento State University political communications professor emeritus.

Although Brown has not been under the same fire Whitman has endured over “Nickygate,” his team seemed just as hesitant in going through with the debate. With tough and unpredictable questions from Owens and the public, KGO officials speculated both sides wanted to avoid the debate altogether.

Owens' producer Mark Silverman said both sides arranged everything in preparation for the debate and even discussed expanding the format.

"Whitman's people suggested the date,'' he said, adding that Brown’s camp agreed to it.

Despite the cancellation, the third and final television debate will still be held Oct. 12 at Dominican College in San Rafael, Calif., and will be moderated by Tom Brokaw.

To reach reporter Susan Shimotsu, click here.

Follow her on Twitter: @susanfromtx.

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