Back when the boll weevil was the scourge of the South's cotton fields, a politician's future could depend on how fervently he denouncd the pest.

But enemies change, and today a successor scourge of Dixie is the bothersome fire ant, a stinging little critter that has become a political figure in its own right.

And since 1958, Congress has spent moe than $97 million to combat this insect. States have developed small bureaucracies to battle it. Members of Congress pledge death to the invader, yet it persists and spreads -- on some 230 million acres in nine states.

Now, a bloc of southern legislators has taken advantage of congressional unhappiness over all types of federal regulation to push through the House another fire ant bill. But this one goes far beyound being a simple blow against the fire ant.

The legislation, designed by Rep. Dawson Mathis (D-Ga.), would authorize the use of Mirex -- a banned pesticide thought to be a cancer-causing agent -- against the fire ant.

In addition, it would remove the Environmental Protection Agency from pesticide regulation after 1985, and in the meantime establish a congressional veto over any EPA pesticide regulations the legislators do not like.

Mathis' language is part of a House Agriculture Committee bill that would extend for one year the Federal Insecticide, Fungicide and Rodenticide Act, the basic law governing these dangerous substances.

The language was adopted by large margins last spring without hearings, although each of the Georgian's proposals provoked intense debate -- including the opposition of Chairman Thomas Foley (D-Wash.) and Eligio de la Garza (D-Tex.), a subcommittee chairman.

The bill, expected to reach the House floor soon for final passage, also has stirred a bitter reaction in the environmental community, which for years has viewed Mirex as a "Public Enemy No. 1."

William Butler, attorney for the Environmental Defense Fund says "they are trading off short-term political programs that are popular for a very real long term cost. It is shortsighted policy. It will expose large numbers of the population to a known carcinogen."

But in the view of Mathis, who says the fire ant can be found in every county in his South Georgia district, these considerations miss the point -- which is that something must be done.

"I'm not that sold on Mirex and I bring this to the floor reluctantly," he said. "But Mirex is very effective when we use it. Nothing else does the job as well to stop the spread of the fire ant."

Mathis said there is "not one iota of evidence" that Mirex causes human cancers, although EPA and most of the scientific community consider it one of the more potent carcinogenic pesticides.

"There's a big difference between potential and actual damage," he said. "There is a broad body of scientific evidence on this thing and the truth is that the jury is still out."

In the view of another Georgian, Rep. Billy Lee Evans (D), the jury is so far out that he once posed before television cameras and ate several mouthfuls of Mirex "to show that it is no great poison," he said.

While Evans did not keel over, he conceded the long term risk. "I feel continued use of Mirex would be questionable and it could tend to cause problems over a period of time," he said, "but we are talking about a limited use of this, with controls."

Evans did not put it in precisely these terms, but he indicated he is under strong pressure from voters in his rural district to come up with a solution to the fire ant plaque.

"Since the cessation of the use of Mirex, almost daily people are telling me the fire ants are back. This is a very big issue with my people. We are at a point where we have to have some assistance," he said.

The pressure felt by Mathis and Evans is similar to that felt by other Deep South legislators, whose states have been invaded by the fire ant. The ant brutally stings humans and livestock and builds large mounds that impede farming operations.

Becasue the congressional seniority system over the years gave Southern legislators special access to the levers of power, the fire ant eradication programs has taken on a life of its own.

According to the U.S. Department of Agriculture, the federal government has invested $97.4 million ineradication and control work since 1958. Affected states have spent about $67.5 million more.

Yet the ant continues to spread -- it began in Alabama about 50 years ago and now reaches into the Carolinas and as far west as Arizona -- and Congress continues to pour money into the program.

The program has found strong support from Sen. Herman Talmadge (D-Ga.), chairman of the Senate Agriculture Committee, and Rep. Jamie Whitten (D-Miss.), chairman of the House Appropriations Committee.

Even though EPA approval of Mirex and a successor, ferriamicide, was revoked, leaving the all-out eradication ware without its traditional ammunition, Whitten's committee has continued high-level funding USDA fire ant work.