“Hello, I am with ABC polls,” a suggested script began.

Some attendees complained that the script seemed deceptive, Ms. Marshner said in an interview afterward. She said that such disguised calls were a common campaign tactic, that it was just a suggested script and that she never recommended answering a direct question with a lie.

Tony Perkins, president of the Family Research Council, who played host to the conference, said he was “upset” to learn of her instructions and condemned any deception.

The Rev. Barry W. Lynn, executive director of the liberal group Americans United for Separation of Church and State, called the tactic “disgraceful” and “a desecration of the church.”

Several organizers at the event lamented that opposition to same-sex marriage, a major catalyst for Christian conservative turnout two years ago, had lost some of its emotional resonance. Massachusetts remains the only state to recognize same-sex marriage. Sixteen states have passed constitutional amendments banning such unions, and eight courts have ruled against the idea.

“Sometimes success brings complacency,” Mr. Perkins said.

To revive some of the emotions around the issue, several organizers said they were taking up the argument that legal recognition of same-sex marriages would cramp the free expression of religious groups who consider such unions a sin  an idea much discussed at the conference.

“That is an issue that wasn’t around two years ago and one that is absolutely moving to the very forefront,” said the Rev. Donald Wildmon, founder of the American Family Association, a conservative Christian broadcaster and advocacy group.

Although that idea may seem far-fetched to many liberal or secular-minded voters, legal scholars across the political spectrum agree that authorizing same-sex marriages could present legal questions for some religious groups. A Roman Catholic group in Massachusetts, for example, recently stopped offering children for adoption rather than provide them to gay couples.