POLITICS / VOICE REGAINED : Birchers Resurge as Communism Fades : Far-right group doubts reality of the upheaval in the East Bloc. It issues alarms on visits by Gorbachev, Walesa and Mandela.

“Aid to Poland? Hold on a minute!”

So said a full-page newspaper ad in the Chicago Tribune last November on the day that Polish leader Lech Walesa visited the Windy City.

“Another welcome mat for Gorbachev? Hold on a minute!”

So read another newspaper ad and a mailing to journalists last month, just before Soviet President Mikhail S. Gorbachev arrived in the United States.

Both alarms, along with similar cautions--most recently, one about Nelson Mandela--were sounded by a voice from the political right that has been silent for so long many Americans probably concluded it had faded out of existence.

But those who think the John Birch Society is dead had better reconsider.

The society says that it has about 50,000 members in 1,000 chapters around the country, with an annual operating budget of $5 million. And this most militant of right-wing groups contends it is mounting a comeback.

Its aim is to expand its influence among Americans who might otherwise assume that the long struggle against communism had ended in victory.

Indeed, the society’s leaders see the fall of Communist regimes and the easing of Cold War tensions as an opportunity to flex their ideological muscle.

“We have taken a more aggressive posture in the last six months,” said Gary Benoit, research director for the society.

In the past, the society relied mainly on local proselytizing by its members, who diligently stuffed mailboxes and wrote letters to the editor. Now, Benoit said: “We’re trying to do things to create a higher profile.”

He cited ad campaigns in major papers and mailings to journalists in Washington and around the country. The campaigns have been tied to such events as the visits of Walesa, who, the society said, “no longer represents the interests of the people of Poland,” and Gorbachev, condemned as “an arch-criminal desperately seeking Western aid to stay in power.”

For Nelson Mandela’s triumphal tour of the United States, the society recruited a black South African anti-communist, Tamsanqa Linda, to visit cities in advance of Mandela’s arrival and denounce him “as a militant communist who pours gasoline on the embers of apartheid.”

Underlying the society’s still-ominous view of world events is the conviction that the import of the recent upheavals in communist countries has been greatly overstated. “Communism has just changed its public relations a little bit,” said Millard Affleck, head of a Birch chapter in northeast Philadelphia.

Besides, Birch leaders say, they always have maintained that the most serious peril to freedom could be found here at home: U.S. leaders whom they see as tools of the communist conspiracy. They argue that this position gives them an advantage over other right-wing organizations in competing for attention and members.

“Those other groups have always focused on Moscow,” said John McManus, public relations director of the society. “The Birch Society has always focused on Washington as the greatest threat.” In fact, the Birch’s Society’s overriding concern--critics say obsession--with the perceived internal threat is what cast the society into disrepute, even among other right-wing groups. Robert Welch, who founded the society in 1958, once called former President Dwight D. Eisenhower “a dedicated, conscious agent of the communist conspiracy.”

That sort of allegation led to widespread denunciations of Welch and the society and contributed to a decline in membership from levels of as high as 120,000 by some estimates. More recently, the election of Ronald Reagan to the presidency apparently caused many conservatives to conclude that the society is no longer needed.

To cut costs, the society trimmed its staff, closed its headquarters in Belmont, Mass., shut down its branch office in San Marino, Calif., and moved to Appleton, Wis., the hometown of the late U.S. Sen. Joseph R. McCarthy--something Birch officers call a “delightful coincidence.”

But the zeal of its members, young and old, has remained undiminished. At the summer camps the society runs for young people around the country, campers still chant their marching song:

“Over hill, over dale,

“We will hit the Commies’ trail

“As we Birchers go hiking along.”

“We give them a solid dose of history and economics,” McManus said of the camp regimen. “But we teach them manners and morals, too.”

Despite its renascence, many conservatives question whether there is room or need for the Birch Society in their movement.

But chapter leader Affleck, who says his chapter has gained about one member a week for the last six weeks, nearly doubling in size, contends that Birchers can cure their image problem with personal contact.

“People who know me say: ‘He may have some some strange ideas, but he’s OK anyway,’ ” he said.