Some Iowa pastors will take part in a protest from the pulpit this weekend. They’re being encouraged to defy I.R.S. regulations and advocate for — or against — specific political candidates in their sermons. Iowa Senator Chuck Grassley, the ranking Republican on the Senate Finance Committee, says he favors letting members of the clergy say what’s on their minds.

Grassley says: "A minister ought to be able to speak politically just like anybody else can. The only thing that I would say, he can’t use the resources of a church or a non-profit organization for political purposes." A conservative legal organization, The Alliance Defense Fund, is encouraging the pastors to jump into the political fray this weekend.

The group hopes to invite investigations by the I.R.S. with an eye to overturning the restriction. Grassley says due to their tax-exempt status, church leaders can’t use the church’s funds to help a candidate.

"But what he wants to say out of his own mouth that doesn’t cost the organization any money, under what freedom of speech of the First Amendment means, he ought to be able to say it," Grassley says. He’s supported legislation in the past that would overturn the I.R.S. restriction, which has been in place since 1954.

Grassley says the pastors have a right to challenge the restriction and invite legal action against themselves as a way to get the law thrown out. Some Iowa churches have joined a United Church of Christ complaint to the I.R.S. hoping to stop this weekend’s staged defiance of agency regulations.