Jamie Wyeth was the curly-haired son of the evening last night when the Corcoran Gallery of Art gave a preview for "An American Vision: Three Generations of Wyeth Art." Young Wyeth accepted cheers for his own pigs, his father's nudes and his grandfather's swashbucklers, and all the 114 or so pictures to be seen in the dynastic exhibition. The show, at its first U.S. stop after a triumphant tour of Leningrad and Moscow, will be open to the public beginning Saturday through Aug. 30.

The evening established that the Wyeths have something for all.

For Sen. Edward Kennedy (D-Mass.), the painting by Jamie of John F. Kennedy was the focus. The pensive portrait was rejected as the official White House portrait. But as the artist and the senator posed for the cameras in front of the painting, Kennedy heaped praise on it. "Magnificent! All the family liked it. It captures his spirit. We know how long Jamie worked on it. It fulfilled our hopes."

After he left, Jamie laughed and said, "Bobby Kennedy hated it. He thought Jack looked as though he were worrying about Bay of the Pigs."

Wyeth said he had not been asked to paint the official Reagan portraits yet, though Nancy Reagan was patron of last night's show and is a known Jamie Wyeth admirer. "Ronald Reagan is an interesting-looking man," said Wyeth, drumming up business. "And she's a terrific subject -- that intense look of hers."

For Wyeth, the paintings by his grandfather were very familiar, though N.C. died in 1945, the year before Jamie was born. "As children, my brother and I dressed up in the costumes he used in his paintings. And I studied art with my Aunt Carolyn in his studios."

He said the Soviets particularly enjoyed the show because of the three generations "and its diversity." Wyeth said he was first famous in the Soviet Union because of his collection of the late Rockwell Kent's paintings and the fact that he owns the house Kent built on Monhegan Island in Maine. "Kent was a socialist. When, because of his politics, his paintings were rejected by a Maine museum, he gave most of them to the Soviets instead."

For editor Ruth Boorstin and her husband Daniel, the retiring librarian of Congress, who saw the show in the Soviet Union, the N.C. Wyeth paintings, many of them book illustrations, "lead children to the books," she said. "All those adventure books, 'Robin Hood' and Robert Louis Stevenson's stories, are still popular."

Susan Baker, in a blue caftan she bought on a trip with her husband, Treasury Secretary James A. Baker III, said the evening "has two big events. We usually try not to go to two in the same evening. But we couldn't resist coming here and we can't wait to see {Washington Post Co. Chairman} Kay Graham's birthday party." Mrs. Baker thought the show was "fabulous." But "to be honest, going to museums is not on the top of my husband's priorities these days."

Pamela Brown, wife of the director of the National Gallery of Art, which has its own Andrew Wyeth show of his longtime model Helga, said she liked the Corcoran show. "All three painters are so different."

Carter Brown himself said, "I loved it. The N.C. Wyeths are dazzling. We've been to Chadds Ford {the Wyeth family home} and we know the collection of George Weymouth, the chairman of Brandywine Museum, well. Still, the show has lots more than I am familiar with."

Jim Duff, director of the Brandywine River Museum, said the Wyeth exhibition in the Soviet Union was the first following the 1985 Geneva cultural exchange agreement.

A string ensemble played the 312 guests up the grand, red-carpeted stairs to the exhibit in the principal galleries, and then back down again for the four-course seated dinner, which was accompanied by three wines. Everything was paid for by AT&T, sponsor of the dinner as well as of the exhibit, which is touring four cities in the United States and five abroad.

As James Olson, chairman and CEO of AT&T, put it, "The Wyeths' century on canvas chronicles America and the enduring value of the love of the land."