As it was , the super pac backing mitt romney , a rival candidate , spent millions on advertisements rubbishing mr gingrich , causing his support to wilt .
Oxbow corp. , a mining and energy company based in west palm beach , fla. , is the single largest contributor to a super pac founded to help mr. romney .
Tom vanden berk , chairman of brady pac of illinois , an anti-gun group , notes that ms halvorson 's nra rating has become a liability , something that would not have happened in the past .
If he could have done one thing to avert his plunge from front-runner for the republican presidential nomination to also-ran , newt gingrich told the press on the eve of the iowa caucuses in january , he would have " pulled the plug on romney 's pac " .
