Despite being embroiled in controversy last week, Herman Cain leads the Republican presidential field by 15 percentage points in Iowa, according to a new poll taken four days after news broke that the Atlanta businessman had been accused of sexually harassing women while head of the National Restaurant Association in the late 1990s. Cain attracts 30 percent support from Iowa GOP caucus-goers, according to the Insider Advantage poll. Former Massachusetts Gov. Mitt Romney places a distant second with 15 percent. Former House Speaker Newt Gingrich rounds out the top three with 12 percent. The remaining candidates poll in the single...