That the freshman senator from Texas had a good night onstage at the latest Republican debate surprises nobody anymore — Ted Cruz is poised, articulate and smart. He's gaining ground in the race for the Republican presidential nomination, and he's positioning himself to capture supporters from Donald Trump or Ben Carson, should either falter. There's still a long way to go in this contest, but Cruz and his campaign are well-funded, well-organized and confident in his ability to outlast and overtake his rivals. Cruz's success is rooted in the idea that there's no such thing as too conservative, both inside...