Quick: What’s the fastest growing religious group in the United States? And the fastest growing (political) party preference of the voting population in California? Well, it’s not the Methodists and it’s not the Republicans, and you probably knew that much already. But would it surprise you at all that the answers are “no-religion” to the first and “no-party-preference” to the second? If you figured as much, you’ve got your finger on the pulse of an important development in our cultural and civic life. One that helps explain, at least to some degree, the continuing and somewhat confounding relevance of Bernie…