COLUMBIA, S.C. — GOP presidential candidate Newt Gingrich is appealing to South Carolina's evangelical Christians with a direct and urgent message: Christians are under attack, and Republicans shouldn't trust Mitt Romney to oppose abortion at all times. "We will not tolerate a speech dictatorship in this country against Christianity," the former House speaker told a crowd of 300 in Rock Hill, S.C., on Wednesday, railing against what he has called government intrusions on Catholic charities and other religious organizations. Gingrich is one of three conservatives, along with former Pennsylvania Sen. Rick Santorum and Texas Gov. Rick Perry, trying to rally...