On the Republican side, anyway, it looks like voters will have a tremendous array of choices. Mr. Cruz, by launching his campaign at a university founded by the late Rev. Jerry Falwell, is signaling his intention to court religious conservatives, in addition to those tea party faithful attracted to his efforts to shut down the government over Obamacare. There will probably be others who play on that turf — former Ark. Gov. Mike Huckabee, for example. There will likely be establishment conservatives like Jeb Bush; up-and-comers like Sen. Marco Rubio; an array of governors, perhaps including Chris Christie, Scott Walker and Bobby Jindal; and some outsiders like retired Johns Hopkins neurosurgeon Ben Carson. The debates, if the party can find a stage big enough, seem destined to produce a healthy contest of ideas about where the Republican Party should position itself in the years ahead.