One reason they aren’t very visible:

Even though Legal Fellow Kelsey Hazzard says she’s personally opposed to capital punishment, it’s just not worth it for abortion rights activists to get involved. “It’s on the decline in most states, so it doesn’t have the same urgency as abortion,” she says.

Hazzard has hit on a central challenge for the conservative anti-death penalty people: Perversely, the very fact that fewer executions happen every year means that very few Americans actually have contact with people in the system. Lack of personal experience makes capital punishment a harder cause for rallying voters than, say, gay rights or pot decriminalization—especially when taking a position either way could be divisive. That’s true even with natural allies, like the younger libertarian followers of Rand Paul, who favors reforming the prison system.