The media role; The Duping of the American Voter, by Robert Spero. New York: Lippincott & Crowell. $12.95.

Welcome to the new quadrennial season of presidential campaign television commercials. If the sneak previews aired during the primaries offer any clue, we're in for the usual blitz of personal attacks, phony issues, and other 10-, 30-, and 60 -second obfuscations of little help in intelligently picking a president.

In the Pennsylvania primary, for example, Carter spots focused on men-in-the-street venting their distrust of Senator Kennedy ("I don't think he has any credibility . . ." "I don't believe him . . . ." "I don't trust him . . . .").

In Iowa, one Republican hopeful (Senate minority leader Howard H. Baker Jr. of Tennessee) saturated the state with commercials showing him pitted in a finger-pointing shouting match with an Iranian college student.

Such affronts to the viewing (and voting) public would be of clinical interest only to television critics and political scientists were it not for the seemingly enormous power wielded by television commercials in electing presidents.

The Carter campaign spent $10 million on television advertising in 1976, or nearly one-half of its entire budget. Similar splurges are being readied for this year's race.

Yet the commercials that influence the choice of the chief executive of the most powerful nation on earth are subject to far fewer government controls than those hawking kitchen cleanser or mouthwash.

"Political commercials are in no way regulated for truth in advertising," observes ad man turned author Robert Spero, "nor can they presently be regulated."

While commercials for consumer products come under the scrutiny of less than nine federal agencies, ads for presidential candidates are virtually unrestricted.

"They are required o meet no broadcast standards of behavior and ethics. They are policed by no government agency. Their political media specialists are beholden to no self-governing regulations. Political advertising is considered 'protected speech' under the First Amendment," Mr. Spero writes.

When the advertising code governing Madison Avenue is applied retrospectively to 24 years' worth of presidential television commercials, he finds few would be allowed on the air. Among Mr. Spero's findings:

* Politically innocent Eisenhower, the first presidential candidate to be marketed on the tube, grossly oversimplified and distorted the issues in the 78 television spots he filmed during one busy day in 1952.

* John F. Kennedy harped on his fictitious "missile gap" theme.

* Lyndon B. Johnson's commercials, crowned by the now-legendary "little girl and the daisy" spot, painted rival Goldwater as a warmonger, while the President himself secretly widened the Vietnam war.

* Richard M. Nixon's ads in 1968 telegraphed veiled appeals to the racist vote.

* Jimmy Carter in 1976 misrepresented his background and accomplishments as governor.

"Nearly three decades of electronic deception, bamboozle, and outright lying, " Mr. Spero concludes. Doesn't the world's leading democracy deserve better?

Of course it does. And the author, after constitutionally ruling out a ban on political commercials altogether, suggests 12 possible remedies.

Samples: deregulating television, lengthening political spots, requiring the candidate to appear in each of his ads (as Presidents Johnson and Nixon rarely did), imposing a political advertising code.

For one proven approach that goes unmentioned in the book, disillusioned American citizen-viewers need look no farther than the land of their political heritage.

In Britain, during national campaigns the two main political parties are each confined to five 10-minute broadcasts. No spot commercials. None.