The communications director of a major abortion-rights lobby group announced Friday that he was resigning immediately, following an announcement by the organization that it would pull an inflammatory TV ad about Supreme Court nominee John Roberts (search).

"I've been thinking for a while that I would most likely leave after the Supreme Court nomination fight was over," wrote David E. Seldin, director of communications for NARAL Pro-Choice America (search), in a letter disclosing his decision to step down.

He said his last day with NARAL was Friday.

"By leaving now I can spend the next two weeks in Cape Cod with my family relaxing, instead of trying to find a place with good cell phone reception," Seldin wrote.

He didn't say whether his resignation was tied to the move by NARAL on Thursday night to yank a commercial linking Roberts to violent anti-abortion activists.

Seldin said he was "especially proud of the leadership role this organization is taking both in the current Supreme Court debate, and in its efforts to change the dynamics of the political debate around reproductive freedom."

Before Seldin's news emerged, NARAL was busy answering questions about why it ultimately decided to withdraw the controversial ad critical of Roberts.

The commercial blasts Roberts, linking him with violent anti-abortion protesters because of the anti-abortion briefs he worked on as a government lawyer.

"We regret that many people have misconstrued our recent advertisement about Mr. Roberts' record," Nancy Keenan, president of NARAL Pro-Choice America, wrote in a letter Thursday to Sen. Arlen Specter (search), R-Pa., who had urged the group to withdraw the ad.

"Unfortunately, the debate over that advertisement has become a distraction from the serious discussion we hoped to have with the American public," Keenan said in the letter.

Specter, himself an abortion-rights supporter as well as chairman of the Senate Judiciary Committee that will question Roberts next month, called the ad "blatantly untrue and unfair" on Thursday.

"The NARAL advertisement is not helpful to the pro-choice cause which I support," Specter said in a letter to Keenan.

Keenan's response said the group will replace the ad with one that "examines Mr. Roberts' record on several points, including his advocacy for overturning Roe v. Wade (search), his statement questioning the right to privacy and his arguments against using a federal civil rights law to protect women and their doctors and nurses from those who use blockades and intimidation."

The original ad has been airing on broadcast television in Maine and Rhode Island and on CNN.

At least one television station had already refused to run the ad. Mike Young, vice president and general manager of WABI in Bangor, said his station ran the ad before deciding to pull it Thursday after receiving a challenge from the Republican National Committee (search).

"After careful, thoughtful analysis, we determined the ad was at worst false, and at best misleading," he said.

Conservatives and Roberts supporters have been calling all week for NARAL to pull the spot.

NARAL had planned a $500,000 campaign to show the ad for two weeks.

"This ad grossly distorts the record of John Roberts from start to finish," said former Judiciary Chairman Orrin Hatch (search), R-Utah. "It has only one goal: to associate John Roberts with violent extremists."

Senate Democrats have not taken a position on the commercial. Sen. Patrick Leahy (search) of Vermont, the Judiciary Committee's top Democrat, told The Associated Press that ads for and against Roberts won't sway senators weighing the confirmation.

"There has been much furor over these ad campaigns, but I believe that television advertisements are not the point, and should not be the focus of debate or discussion," Sen. Charles Schumer (search), D-N.Y., said Thursday. But Schumer said he would ask Roberts about the constitutionality of abortion clinic protesting at his confirmation hearing.

In 1991, Roberts helped write — on behalf of the government — a Supreme Court brief in Bray v. Alexandria Women's Health Clinic. In that case, the court limited the federal help available to abortion clinic owners who seek to stop blockades by protesters.

FOX News' Catherine Donaldson-Evans and The Associated Press contributed to this report.