Newt Gingrich refutes claims by his second wife, Marianne Ginther, that he demanded that they have an open marriage so that he could continue an affair with Callista Bisek, who later became his third wife. The accusations, aired on ABC News on Thursday, come just before the Republican party's South Carolina presidential primary. If true, the allegations would mean Gingrich was having an affair whilst pillorying President Bill Clinton over his involvement with Monica Lewinsky.