NEW YORK (AP) _ Advertisers are showing less backbone when faced with complaints about their sponsorship of TV programs and editorial projects that some groups find offensive, a constitutional rights advocate says.

But Arthur Kropp, president of People for the American Way, said companies are being shortsighted by caving in to such complaints.

''They are not going to be able to sweep these people under the rug. They will find they are in a constant battle with them,'' he said.

On Thursday, two advertisers canceled plans to run commercials on NBC's popular ''Saturday Night Live'' program after hearing from a Christian group that pointed out skits in recent episodes that it found offensive.

Ralston Purina Co. confirmed that it had dropped plans to run about $1 million in ads on the program starting in April because it felt one of the shows ''crossed over the line of good taste.''

General Mills Inc. said it had canceled an undisclosed number of ads on the show after reviewing the other episode.

Both companies said they had heard complaints about the program from others as well as the Christan group, the American Family Association of Tupelo, Miss.

The Rev. Donald Wildmon, who heads the group, has campaigned for more than a decade against what he sees as pornography and excessive violence in magazines, TV and movies.

Last summer, CBS cut 3 1/2 seconds from an episode of ''Mighty Mouse'' after Wildmon said the scene gave the impression that the cartoon hero was snorting cocaine. CBS said he was sniffing flowers.

The ''Saturday Night Live'' case provides another example of increasing activism by individuals and groups that are trying to end shows they don't like by urging advertisers to quit buying commercial time on them.

Kropp said he understands why companies trying to make a profit take their ad dollars elsewhere when an activist group complains or threatens a boycott.

''It is much easier to pull ads and avoid controversy. These companies are not in the business of defending the First Amendment,'' Kropp said.

But he said the trend could have a dangerous chilling effect on the media.

The American Family Association said it had pointed out two ''Saturday Night Live'' episodes it found ofensive to Ralston and General Mills and was later notified they each had canceled ads on the weekly comedy show.

In one episode, a skit was apparently designed to see how many times the actors could say ''penis'' on network TV.

Patrick Farrell, a spokesman for St. Louis-based Ralston, said Ralston canceled about $1 million in ads on the show for its Eveready Battery Co. because of the skit.

Farrell said Ralston had been a sponsor of the program for a number of years and knew it was sometimes controversial and aimed at an audience of young adults. But he said the skit ''crossed over the line of good taste.''

In the second episode, a skit featured use of the words ''funk'' and ''funking'' as euphemisms for profanity.

Terry Thompson, a spokesman for General Mills in Minneapolis, said ''some commercials were canceled'' on the show after the episode was reviewed. He declined to say many ads were pulled.

But he said the company's current absence from advertising on the program ''reflects scheduling fluctuations and nothing else.''

A Michigan housewife, Terry Rakolta, recently captured national attention with her letter-writing campaign to advertisers who sponsored the program ''Married ... with Children'' on Fox Broadcasting Network.

Rakolta complained about sexual innuendo and the treatment of women in the popular program, a comedy about a blue-collar family.

Since she wrote, big ad spenders such as Procter & Gamble Co., McDonald's Corp., Tambrands Inc. and Kimberly Clark Corp. have instructed their ad agencies not to buy time on the show.

Last week, Wildmon said the American Family Association was calling on consumers to quit drinking Pepsi for a year to protest the soft drink maker's refusal to cancel its advertising contract with the entertainer Madonna.

Wildmon said his group felt Madonna's latest music video, produced separately from her Pepsi ad, contained offensive sexual imagery.

The American Family Association publishes a monthly Christian magazine that claims a circulation of 380,000.