Just as Americans are debating whether untamed political rhetoric inspired the shooting of a congresswoman in Arizona, the founder of a project to promote civility in politics is calling it quits because only three elected members of Congress agreed to sign a rudimentary “Civility Pledge.”

Mark DeMoss, a Republican and a prominent evangelical Christian who runs a public relations firm in Atlanta, initiated CivilityProject.org in January 2009 because of alarm over what he saw as the increasingly vicious tone in American politics. He asked his friend, Lanny J. Davis, a Jewish Democrat and a lobbyist who worked for President Bill Clinton, to join the effort.

They sent out 585 letters asking every sitting governor and member of Congress to sign a pledge that said:

I will be civil in my public discourse and behavior. I will be respectful of others whether or not I agree with them. I will stand against incivility when I see it.

Mr. DeMoss said he in an interview that he is now folding the project after spending two years and about $30,000 in expenses on the endeavor. Three legislators had signed the pledge. They were Senator Joseph I. Lieberman, independent of Connecticut; Representative Frank Wolfe, Republican of Virginia; and Representative Sue Myrick, Republican of North Carolina.

In a letter written on Jan. 3 to the three, Mr. DeMoss said, “I must admit to scratching my head as to why only three members of Congress, and no governors, would agree to what I believe is a rather low bar.”

Mr. DeMoss, a former aide to Moral Majority founder Rev. Jerry Falwell and an unpaid adviser to Republican Gov. Mitt Romney in the 2008 presidential campaign, said that he was particularly surprised by the hostility to the civility pledge from conservatives.

“The worst e-mails I received about the civility project were from conservatives with just unbelievable language about communists, and some words I wouldn’t use in this phone call,” he said. “This political divide has become so sharp that everything is black and white, and too many conservatives can see no redeeming value in any liberal or Democrat. That would probably be true about some liberals going the other direction, but I didn’t hear from them.”

Mr. DeMoss said he was not convinced that there is a link between vicious political attacks and violent acts, but he added, “Whether or not there’s violence, whether or not incivility today is worse than it’s been in history, it’s all immaterial. It’s worse than it ought to be.”