The McCain campaign has vigorously denied a report in the National Enquirer magazine, that the Republican's vice-presidential pick, Alaska Governor, Sarah Palin has had a steamy extramarital affair with her husband's business partner.
The story, which appeared just hours before Governor Palin was due to address the Republican convention was branded "scurrilous" by the chief strategist, Steve Schmidt. He said it was totally untre.
"The smearing of the Palin family must end. The allegations contained on the cover of the National Enquirer insinuating that Gov. Palin had an extramarital affair are categorically false. It is a vicious lie," said McCain senior adviser Steve Schmidt.
"The efforts of the media and tabloids to destroy this fine and accomplished public servant are a disgrace. The American people will reject it."
It follows revelations earlier in the week that her 17 year old daughter, Bristol, was five months pregnant and planned top marry the father Levi Johnston and have the Baby.
Governor Palin is expected to castigate the media in her speech at 12.30pm Eastern Australian time.
The magazine, has a reputation for digging dirt on politicians lives. It insisted that Democratic presidential candidate, John Edwards was having an extramarital affair and had had a child with his lover, while his wife was ill with breast cancer. The allegations were denied for months until the national Enquirer finally got pictures of the duo meeting in a hotel in Los Angeles.