Chief of Staff Howard Baker, bantering with reporters at the White House dinner for Japanese Prime Minister Yasuhiro Nakasone, insisted he has no interest in moving into the White House as First Tenant after Ronald Reagan leaves.

"I denied that," Baker said to ribbing about rumors that he likes the White House so much he's decided not to leave. Standing to one side, taking it all in, was a bemused Reagan.

"He says I can't answer any questions," Reagan told reporters who tried drawing him into the dialogue about whether Baker is going to dust off his candidacy and run for president.

"After the president saw my office and the nice patio off it he said, 'I like this one better,' " Baker said, referring to the attractive garden-style White House office reportedly created for his predecessor Donald Regan.

"Well," suggested a reporter, "maybe you could swap offices."

What chance does a bachelor or a widower have of becoming president?

Not much, says Betty Boyd Caroli, the Kimbrough Community College (City University of New York) professor who spent four years researching and writing a history of presidents' wives that Oxford University Press has brought out under the title "First Ladies." (Not to be confused with Catherine Breslin's new novel of the same name just published by McGraw-Hill. Breslin's is a fictitious account of two not-so-thinly-disguised political wives, one an alcoholic married to a philandering liberal from a prominent Philadelphia Irish family, the other the wife of a former conservative governor who played cowboy in Tinseltown before entering politics.)

Caroli thinks that for an unmarried man to win the White House, "there would have to be a very good reason that the candidate didn't have a wife -- that she just died, for instance." Wives have been important in American politics since Martha Washington, a tradition that "really goes back to the fact that we didn't have a queen so we had to have somebody."

Similarly, Caroli says, a woman running for president will have to be married.

"I think we're not going to elect a woman to any high office who does not have a husband," she says. "We have great suspicions about people who run who don't have husbands or wives."

She thinks Americans will scrutinize a candidate's husband more than they will a candidate's wife because most women married to politicians are still performing the traditional roles of helpmate rather than cobreadwinner. She sees a husband's occupation as a critical factor in his wife's campaign.

"So he'll probably be a professional of some type, something like a lawyer or a teacher or a doctor. He won't be in real estate," she says.

Caroli also thinks a president's husband would refuse to do many of the ceremonial jobs that presidents' wives have taken on through the years and that as a result some of the tasks might have to be turned over to paid White House staff members.

She says she believes a president's spouse could continue to work, while living in the White House, if the career field posed no conflict of interest. But even within acceptable fields there would be limits.

"A noncontroversial doctor, perhaps, somebody with a private practice who is not getting grants or associated with a particular hospital," Caroli says. "Or a writer who didn't publish anything until the president left office. Even a singer becomes a political problem."

Since a president's husband (question: If a wife is a First Lady would a husband be a First Gentleman?) is still some time off in the future, Caroli predicts that the wife of the next president will be stylishly dressed, photogenic and thin.

"Somebody said I should write about the anorexic styles of political wives but I decided not to," says Caroli, who is watching to see if Barbara Bush goes on a diet. "But I don't think she will. And she hasn't dyed her hair."

Notes Caroli, whose next book will be a biography of Lou Hoover, "Wasn't it Lady Bird {Johnson} who said, 'If I'd known where I was going to end up I'd have changed my nose and my name'?"

(And if that doesn't cover the subject for you there is yet a third book about a first lady just out. This one is an unauthorized biography called "The Search for the Real Nancy Reagan," written by Frances Spatz Leighton and published by Macmillan.)

Call it the Luck of the Liberals that the 1987 Public Interest Follies is hitting the boards at George Washington University's Marvin Center Theatre the same week that the Iran-contra hearings get underway on Capitol Hill.

Not that "We the Follies (The Unauthorized Salute to the U.S. Constitution Bicentennial)" will be stuck on Irangate when it opens Thursday and continues nightly through Sunday. This being Washington, where the show has been going on nonstop for 200 years, "Follies" is a bicentennial retrospective of foolishness at the top -- from Ronald Reagan ("Will the real Ronald Reagan please stand up?" goes one reprise) and Ed Meese (singing "Judges -- What Are They Good For?") to Fawn Hall (and her School for Secretaries faculty of Rose Mary Woods and Rita Lavelle) and Oliver North (singing "Irani" in "North Side Story").

True to the Follies' decade-old tradition, irreverence is the operative word, serving as a release valve for a lot of talented do-gooders who spend the rest of the year raising money for the nonprofit organizations that employ them.

Or as Follies cofounder and artistic director Byron Kennard, an environmentalist who worked for Lady Bird Johnson's beautification program back in the 1960s, explains it: "It gets them out of the contest of institutional competitiveness."

Unlike what do-gooders usually do, however, these do-gooders spend what proceeds are raised every year on the Follies.

"Everybody in it is involved in raising money where they work," says Kennard. "Can you imagine what would happen? We would destroy ourselves trying to decide which cause would get the money."

After 10 years, the Follies has a $5,000 reserve, says Kennard. "It permits us to make -- and keep -- commitments."

Another follies, the Capital Canine Follies, has landed Boxcar Willie Reagan-Revell as top dog for its June 6 fundraiser. In so doing, Willie is following in the pawprints of his more illustrious relative, Rex Reagan, who chaired last year's fundraiser for the Capital Children's Museum but did not attend.

Willie, however, is known to be a working chairmutt, and prospects are good that he will join other top dogs vying for recognition and ribbons at the annual show. Alluding to his lineage in an invitation to other prospective pawticipants last week, Willie wrote that "My cousin, Rex Reagan, is Honorary Petron and my parents, Maureen {Reagan} and Dennis {Revell}, are tickled to the bone about my Chairmuttship!"

There are those who would argue that if Boxcar is Son of the First Daughter then he is also Ronald Reagan's grandson and Rex Reagan's nephew, not his cousin.