SPARTANBURG, S.C. — Newt Gingrich signaled Wednesday that he believes his criticism of Mitt Romney’s record at Bain Capital is a mistake — and that he’s created an impression that he was echoing Democratic rhetoric. Gingrich conceded the problem when pressed by a Rick Santorum supporter at a book-signing here Wednesday. “I’m here to implore one thing of you. I think you’ve missed the target on the way you’re addressing Romney’s weaknesses. I want to beg you to redirect and go after his obvious disingenuous about his conservatism and lay off the corporatist versus the free market. I think it’s...