There is lots of evidence to support this as Potok details. I would like to elaborate a bit on my quotes in his story:

Frederick Clarkson, an independent journalist who has written about the American religious right for a quarter of a century, notes that the social conflicts set off by Roe v. Wade and Brown v. Board of Education continued for decades after the Supreme Court ruled. Moderating public attitudes toward homosexuality, he says, are viewed by the religious right as "symptoms of a society that has fallen away from God's laws, seriously enough that God is ready to smack the country down."

After all, to the hard core of that anti-gay religious right, Clarkson says, "homosexuality is a profound capital offense against God's order."

The significant backlash and ongoing religious and ideological opposition by profoundly motivated groups and individuals is unsurprising.  To understand how that could be so, one need look no farther than Rachel Tabachnick's recent essay at Talk to Action titled The Rise of Charismatic Dominionism which explains the 20th century transition of many evangelicals from apoliticality to political militancy.

Significant but under-reported, is the reinvention of the Religious Right, which is in an era of transition as the founding generation of leaders pass from the scene.  This sometimes rocky transition has been going on for at least a decade. The deaths of Jerry Falwell, D. James Kennedy and R.J. Rushdoony; and semi-retirements of James Dobson, Don Wildmon, Beverly LaHaye, and Pat Robertson have not proved to be indicators of the death or retirement of the Religious Right itself. We saw, for example, the groups behind The Manhattan Declaration and The Call team-up with Newt Gingrich to mobilize during the fall election campaign with an aim towards reinventing the Religious Right itself.

What is interesting and significant is not the death knell of the Religious Right, endlessly (and falsely) retolled -- but the new Religious Right that is emerging from the old.