The Congressional Club had its annual lunch yesterday, and as far as ladies' lunches go, it was absolutely amazing. A ballroom of 12,000 red roses! A runway where you could see political wives promenade on the arms of red-suited Marines! A Sousa march for Nancy Reagan, introduced as "The First Lady of the Land!" Ginger Rogers singing "42nd Street!" And 1,380 women, all dressed up in white suits, freshly shaped hairdos and glimmering pink nails!

They're already making plans for next year.

"You can't believe the work," said Nancy Hefner, president of the club. Her husband is Rep. W.G. (Bill) Hefner (D-N.C.) "It truly is a labor of love. Members of our club came and put roses in 1,400 bud vases. I mean, literally."

The club is an organization of House and Senate wives, and seems to have been around forever. This year it's celebrating its 75th anniversary, and the lunch, as always, is the highlight of the year. Even when other ladies' lunches were withering in the late '60s, this one was blooming. Looking around the Shoreham Hotel ballroom yesterday, you would have wondered if the '60s had occurred at all.

"We honor the first lady--nothing more or less," said Hefner. In essence, it is a break-even pep rally. The $20 tickets, checks from corporations such as Dow Chemical and in-kind donations from America's rose growers pay the bills, including $3,000 that the club gives to charity. Club members can invite two guests, so people actually fly in from all over the country. The draw is not the lunch (watercress soup, chicken breast and strawberry tart) but the first lady. Everybody wants to get a look at her.

And a few want to get pictures. Margaret Watson, a friend of Hefner's from Vienna, Va., had brought her Instamatic with her and was having a hard time deciding if she should get out of her seat to take the snapshot. "Do you think it's tacky to stand up?" she finally asked Gretchen Poston, the former social secretary to Rosalynn Carter.

Poston didn't think so, and Watson got her picture.

After the strawberry tart, Nancy Reagan had a few things to say.

"The roses are so pretty," she observed. "And I'm so glad I wore my red suit." (Short sleeves, slightly tucked at the waist, no blouse, gold necklace, a small bag slung over her shoulder and across her chest.)

She also marveled that the ladies had kept the entertainment--Ginger Rogers, who wore hot pink--under wraps.

"Now, I wonder how they keep these secrets from leaking," she said. "When I find out, I'm going to tell my husband." Everybody laughed.

And then: "Thank you very much--I really enjoy this every year."

That was pretty much it.

Afterward, everyone took home party favors--Chanel perfume, makeup, a scarf, a compact mirror, tea rose-and-glycerine soap, the roses in the bud vases--and thanked Hefner on the way out.

"You did a beautiful job!" said one guest.

"Oh, aren't you nice," said Hefner.

"I didn't think Nancy would eat--but she did," said the guest.

"Yes, she ate most of her strawberry tart," said Hefner, who sat next to her.

Then everybody went out into the spring sunshine to catch taxis or limousines.

"Somehow each year's luncheon is lovelier than the last," said Hefner from the podium.

It's hard to imagine what it'll be like next year.