I think that talking about the value of different epistemological preferences in terms of civic responsibility is the way to go. Let us forget for the moment who is right and who is wrong about the resurrection of Christ, I frankly don't care to have that conversation ever again. Lets talk about who's a responsible voter and who isn't.
Are your methods for evaluating who you vote for any damn good? Do you know why you believe the things you do? Do you know why the authorities you trust say the things they do? These are much more actionable questions that might even be more tolerable to hear from an opponent.