Well, I'd want to notice the attitude of the person I'm talking to, before responding. I could imagine a sincere attitude as one possible one (instead of cynical or mocking). If sincerely stated, the person may honestly believe (not just a rhetorical attack) that Christians are maybe just superstitious people.
In that case, you have a chance, with such a sincere person, to tell them a more real thing. I'd want to give them a powerful hint of how wonderful the things Christ said are, so that they might go and read more for themselves. Depending on the person, there are a variety of ways that could sound, and so this is only one of a great many possibilities:
"Aren't Christians really just superstitious?" [if asked sincerely]
One answer: "It could seem that way from a distance, and some in any city probably are. But what motivates most Christians is instead that they want to learn more from the Teacher who said such things as "Love your neighbor as yourself", and even said "Love your enemy" -- they want more of what He has to teach, and there is very much more. That's why Christianity is so popular around the world through the centuries, in any nation where people hear some of it. "
Here we've recognized the partial truth in their point of view, but also given them a strong hint of the actual reality, and even better, some of the actual Word of Christ.
Key thing: the actual Word is always better than any representation or partial paraphrase of some bit.