Ever since Ronald Reagan's election in 1980, the many enemies of Ralph Nader have been licking their chops in anticipation of the consumer movement's demise. And the pro-business administration has indeed served them slices of Naderism for breakfast, lunch and dinner.

But despite a number of setbacks, Nader and the activism he inspired have managed to survive more or less intact. In fact, one of his most controversial creations has risen almost Lazarus-like from the grave so gleefully dug for it by corporate freebooters and conservative ideologues.

The Public Interest Research Groups, or PIRGs, are Naderism in its purest form, spinoffs founded in 1971 by the guru himself and Donald Ross. Concentrated on college campuses, PIRGs file lawsuits, get consumer issues on the ballot, lobby Congress and state legislatures, canvass voters and -- as the name suggests -- do research that exposes corporate abuses. It's no wonder that these pesky kids were top-priority targets of conservatives emboldened by Reagan's ascendancy.

And the PIRG purge had some initial success. By 1984, the movement's 24 state groups on 100 campuses had dwindled to 20. Student membership was down.

The conservative College Republicans urged students to "rid their states of this pestilence." Our associate Les Whitten learned that conservative business and professional outfits such as the Edison Electric Institute, the American Nuclear Energy Council and the National Legal Center were pushing the PIRGs determinedly toward oblivion, with the eager support of several self-interested corporations.

The future looked bleak for the PIRGs. But a funny thing happened on the way to the altar: The sacrificial lambs declined to cooperate with their executioners. They perversely proceeded to grow instead.

There are now 25 active state PIRGs, which count not only 500,000 student members on 115 campuses, but another half million among the public at large. A book on the PIRG movement, "More Action for a Change," by former Nader associate and Jack Anderson reporter Kelley Griffin, is due out this month. It provides both history and how-to for potential PIRG organizers.

Among the PIRG success stories Griffin salutes are those of Jill Siegel, who at 19 lobbied successfully for a New York law that protects hearing-aid customers from unscrupulous hucksters; Marsha Gomberg of Oregon, who posed as a patient to expose Medicaid fraud, indexed trees and wildlife to help put through a state wilderness-protection law and organized doctors to lobby against homicidal herbicides; and Karim Ahmed, doctoral candidate and father of two, who found time to organize a Minnesota PIRG that persuaded the legislature to enact an asbestos ban.

PIRGs have lost as many battles as they've won, but they keep on coming back. And their victories have been impressive, resulting not only in protection for the public but in punishment and great expense for the special interests they have challenged.