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Under current tax law, pastors and other religious leaders whose congregations are classified as 501(c)(3) tax exempt organizations are required to keep politics to a minimum at official church functions. Though they do not have to keep entirely mum, "no substantial part" (a vague term often interpreted as between 5 and 20 percent) of the organization's spending and activities can attempt to influence legislation or campaign outcomes.

However, at least 1,800 pastors nationwide feel that they should be able to guide parishioners politically while on the pulpit. They are participating in an event called "Pulpit Freedom Sunday," which is actually a month-long project organized by the conservative nonprofit Alliance Defending Freedom. Participating pastors say they will "[represent] biblical perspectives on the positions of electoral candidates."

The role of the church in politics was a long-debated theological question long before it was a tax issue. In 2006, Minnesota megachurch pastor Greg Boyd received national media attention when he refused to endorse a presidential candidate or advance other political causes at church, a decision that cost his church about one thousand members.