According to the American Religious Identification Survey, about 15 percent of Americans identify as "none" when asked for religious identity, almost double the number who did so in 1990. Thus, the improved prospects of a theoretical atheist presidential candidate -- up from only 18 percent when the question was first asked in 1958 -- reflect progress for America's seculars.

This newfound tolerance for secularity is reaching the highest levels. President Barack Obama has included nonbelievers several times in his description of American pluralism, including a direct reference in his inaugural address. Secular groups also scored a victory in 2010 when they met withWhite House officials to discuss policy issues of concern to them -- the first such official recognition of American nonbelievers ever.

Perhaps nothing demonstrates the momentum of secularism more than the Secular Student Alliance, the national umbrella organization for college atheists, which has expanded from just a few dozen campus groups in 2007 to more than 350 today. Last year the alliance began venturing into high schools, a move that is sure to further normalize atheism at the grassroots level.

Secular activists like to describe their movement in terms of what it stands for -- reason, critical thinking, science and ethics -- but the movement can perhaps best be understood by what it stands against: the overbearing influence of religious conservatism in America. In fact, the fast growth of the modern secular movement in many ways reflects a new form of opposition to the religious right.

Although the religious right has always had opponents, most of its adversaries haven't been very effective. Since Jerry Falwell's newly formed Moral Majority helped elect Ronald Reagan in 1980, politically engaged religious fundamentalists have exerted more influence with virtually every election cycle, while few efforts to slow down the juggernaut of the Christian right have been successful.