Religion

because it's both diverse (not in lockstep, so part of the left will deal with abortion and another, overlapping, part, with civil rights) and because it doesn't have a big flashing neon sign that says, "Religious Left."

Objections have been noted that the religious left isn't organizing voters.

Would people consider civil rights to be a bigger issue on the left than the right?

Are black churches religious?

Do black churches mobilize voters-registering them, having GOTV drives, even driving voters to the polls?

In many ways, they are part of the religious left. But only part and partially.

It's largely the same with a lot of the "religious right". They don't march in lockstep. They have this nifty PR campaign that ended a couple of decades ago to convince outsiders that they do march in lockstep. It's an exaggeration. But it was so successful that not only do people did believe the exaggeration, but 20 years later they still parrot it.

Note that in some ways, many black churches are also part of the "religious right." But again, branding isn't always accurate so they're not "religious right" for branding purposes--and the branding is deceitful in that it masks a lot of diversity.