GREENVILLE, S.C. -- Many of the Republican presidential candidates descended Friday on Greenville ahead of Saturday's CBS debate.But only one was savvy enough to get himself enlisted as the opening act of a throbbing, trembling Christian rock concert that packed 14,000 evangelicals into a downtown arena on Friday night.So here came Ted Cruz, striding onto the catwalk of a stage, beaming under the spotlight, leading the crowd in prayer, asking them to unite behind him in next Saturday's primary election, and jumping up like a basketball player high-fiving fans as he walked into the locker rooms in the bowels of...