One of the pitfalls of political campaigning is telling a joke to an audience that, unbeknownest to the teller, has just heard it. If the person who told it happens to be an opponent, so much the worse.

That's what happened to Sen. Albert Gore Jr. (D-Tenn.) the other day. He drew nothing but nervous titters when he told a tale designed to illustrate the indignities of being a little-known presidential contender. It had to do with going through a food line at a political function, asking for extra butter and being turned down. "You don't seem to understand, ma'am," Gore told the story on himself. "I'm running for president of the United States."

"No, you don't understand," comes the punch line. "I'm the lady in charge of the butter."

Moments before, out of Gore's earshot, presidential rival Bruce Babbitt had told the story (in his version, it was a piece of chicken, not a pat of butter) to the same group of southern state legislators -- with better results.

Gore has had his share of woe about joke authorship in the campaign. Rep. Morris K. Udall (D-Ariz.) gently rebuked him this spring for stealing a Udall classic from 1976. But when informed by someone in the southern legislators' audience that Babbitt had beaten him to the punch line, Gore barely skipped a beat. "Well, you know where he got it from," he said, feigning indignation.