New Jersey Gov. Chris Christie (R). (John Gress/ Reuters)

One key line of attack against the Republican party's top presidential contender, New Jersey Gov. Chris Christie, revolves around his conservative bona fides: Is he or isn't he?

Democratic officials want to paint him as a right-wing, hard-line conservative. But Christie's potential rivals want to slap him with a different label: moderate. Kentucky Sen. Rand Paul, another GOP contender, used that word to describe Christie this week, adding that it would be difficult for a moderate to carry key conservative states. So which does Christie prefer? Neither, he says.