Palin reached the final controversially ahead of other celebrity contestants, who were widely regarded as better dancers. Her inclusion, along with actress Jennifer Grey and actor Kyle Massey, became a point of strong disagreement among fans of the top rated American television programme.
She has been strongly backed by her mother Sarah Palin, the former Republican vice-presidential candidate, conservative radio hosts and members of the Tea Party political movement. But she received death threats as has her professional dance partner Mark Ballas, 24, who grew up in Britain.
Security was heightened ahead of the final show and producers were considering not allowing them to appear in Times Square in New York afterwards, as is usual at the end of a series. Ballas was also told to stop contributing to social networking websites, as his comments could inflame people. Programme staffs were put on 'high alert'.
"Security is on absolute lockdown. Bristol is surrounded by security guards everywhere she goes," the Telegraph quoted a staff as saying.
Last week, a threatening letter with white powder was received at the programme's production offices and the FBI was called in. Tests showed it was talcum powder.