The electronic mud is about to fly in the election campaign, with both President Carter's and Ronald Reagan's campaign staffs preparing negative television commercials impugning their opponent.

The first anti-Reagan commercial produced by the Carter campaign ran Thursday night during the CBS Movie, "A Piece of the Action." The commercial showed the Oval Office with no one in it, while an announcer read this message:

"When you come right down to it, what kind of person should occupy the Oval Office? Should it be a person who, like Ronald Reagan, has a fractured view of America? Who speaks disdainfully about millions of us as he attacks the minimum wage and calls unemployment insurance a 'prepaid vacation'? Or should another kind of man sit here, an experienced man who knows how to be responsive to all Americans, all 240 million of us? Figure it out for yourself."

Gerald Rafshoon, the campaign man responsible for Carter's advertising, said yesterday the ad had run because of a slipup in his own organization. He had not intended to begin broadcasting commercials critical of Reagan until later, Rafshoon said.

In the Reagan camp, advertising man Peter Dailey, Rafshoon's opposite number, told reporters yesterday that two anti-Carter spots will begin running next week. Though he had a dozen new commercials to show the reporters, Dailey said he left copies of these two in New York. They will show graphs depicting economic conditions during the Carter administration, with a commentary quoting early Carter promises and later economic developments.

Both camps insist that negative ads won't be a major part of their commercial campaigns, which will cost each side $15 million to $17 million by Nov. 4."We don't have plans to do any extensive negative ads," Rafshoon said yesterday. He said the Oval Office spot on Reagan "is really not negative -- it's just pointing out Reagan's record, as we expect ours to be pointed out."

Dailey told reporters that the Reagan camp will repeat a series of about a dozen commercials in the days ahead, trying to put a strong pro-Reagan message into the national consciousness.

Dailey was particularly pleased with new commercials emphasizing Reagan's accomplishments as governor of California from 1966 to 1974. These spots, some five minutes long, others just a minute, show film of Reagan as governor, while an announcer boasts of his achievements.

"In 1966 he was elected governor of the state of California, next to president of the biggest job in the nation. What he inherited was a state of crisis. California was faced with a $194 million deficit and was spending a million dollars a day more than it was taking in. The state was on the brink of bankruptcy. Working with teams of volunteers from all sectors, Governor Reagan got things back on track. His common-sense style and strong, creative leadership won him a second term in 1970. Governor Reagan was the greatest tax former in the state's history. His program included property tax relief, reduction of sales taxes and tax rebates totaling nearly $3 billion. . . ."

Dailey said Reagan organization polls showed that this sort of message makes a strong impression on voters. Reporters who have done door-to-door canvassing in recent weeks also report that people who have an impression that Reagan was a good governor tend to be more sympathetic to his candidacy.

Dailey said the spots on Reagan as governor will be repeated often. "We want to run that documentary until people here [at Reagan headquarters] get so sick of seeing it that it may begin to penetrate" public consciousness.

The Carter camp is aware that Reagan can score points with voters if they get the impression that he was a good governor. Therefore, Rafshoon is preparing ads similar to ones produced by Gerald R. Ford's media advisers, the firm of Bailey-Deardourff, in 1976 to try to weaken Jimmy Carter's presidential bid.

Those commercials showed men and women on the street in Georgia telling the television camera that Carter actually had been a lousy governor. This year, Rafshoon is planning people-on-the-street interviews in California that make the same point about Reagan's tenure in the statehouse in Sacramento.

Rafshoon has produced more than twice as many commercials as Dailey so far, including a batch of new ones featuring Carter in informal conversations with a group of women in a backyard in Alexandria, a group of old people in a Washington home for senior citizens and construction workers at a building site in Rockville. The ads depicted a relaxed president chatting about his accomplishments and hopes for the future.

In general, the Rafshoon ads seem of higher technical quality than those Dailey has made for Reagan, many of which use snippets from film clips of Reagan speeches where the sound track was poor. Dailey has already tossed out the first commercials he made, changing the campaign's message in the process. For example Reagan's economic spots now emphasize inflation as the preeminent economic problem; earlier ads had a more complex message on the economy.