DES MOINES - Republican presidential candidate Mike Huckabee has yanked the television ad that would have been his first over-the-air attack on the record of his top rival, Mitt Romney.

Huckabee, the former Arkansas governor, said he decided Monday not to air the ad because he didn't want to further degrade a campaign that has already been overrun by Romney's negative ads. The Huckabee ad had been delivered to Iowa television stations and was supposed to begin later that day, just four days before the caucuses.

"About an hour ago, I just decided that's not the way we're going to run things," Huckabee said at a news conference that had been scheduled to promote the ad. He said some of his top aides didn't know of the change of plan until moments before he walked onto the stage.

"If you gain the whole world, but lose your own soul, what does it profit you?" he said, paraphrasing the Gospel of Mark.

While the ad won't appear on television, Huckabee did show it at the news conference. The spot accuses Romney of raising taxes and providing support for abortion as governor of Massachusetts and then misleading voters about what really happened.

"If a man is dishonest to obtain a job, he'll be dishonest on the job," Huckabee says in the ad.

Huckabee said he decided to do one public showing of the ad to respond to the possibility that rival campaigns would claim the ad didn't exist.

Romney spokesman Tim Albrecht said Huckabee is trying to have it both ways, by withdrawing the ad while still showing it to the news media.

"To say one thing one minute and then turn around and show an attack ad to reporters the next will, obviously, leave folks with a very cynical view of Mike Huckabee and his message," Albrecht said.

At the news conference, reporters asked Huckabee if he was trying to have it both ways.

"If people want to be cynical about it, be cynical about it," he said.

Steve Roberts, a Des Moines lawyer and a member of the Republican National Committee, said he has never seen anything quite like Huckabee's decision about the ad.

"People over and over say, 'Why do we have to have this negative campaigning, why do we have to be against the other person?'" Roberts said. "But we've seen that (negative campaigning) often works. … We'll see what happens here."

Contact Dan Gearino at (515) 243-0138 and dan.gearino@lee.net.