Something strange is happening in the vice president's cabin as his jet flies from Chicago to Washington. Al Gore is uncharacteristically animated. One might even say, if such words can be used, that he is "goofing around."

"Want to see what happens when you have a military contractor get you a VCR?" Gore asks a visitor, then leaps to his feet to demonstrate the custom-built Air Force Two machine. It is a baffling assortment of flashing colored buttons and mysterious commands. "Whichever one you press, it's the wrong one," Gore says, trying several buttons until a flashing airplane appears, but no movie. "It's perfectly logical," he says, chortling. "It's like that Simon Sez game without the music." Next, he demonstrates how he dislodges his TV screen from the ceiling--with a bent paper clip.

What's the source of this seldom-seen Gore mirth? Well, it appears to have something to do with the other gentleman sitting in the cabin with an impish grin, an aw-shucks manner, an Al Hunt hairdo and a Sam Adams beer in hand. The man is Frank Hunger, the husband of Gore's late sister.

Those watching Gore closely may notice a difference in the candidate's mood lately. This may have something to do with a rise in the polls. But you can't dismiss another recent change for Gore: his brother-in-law's decision to take a leave from the Washington office of the Long, Aldrich & Norman law firm to travel with Gore. Often wearing rumpled blue blazer, khakis and incongruous wingtips, Hunger spends most every waking minute with Gore. He gets off the plane right after Gore at each stop and joins the candidate in his armored limo. Frank Hunger is, by all accounts, the number one fan of the man from Tennessee.

"Frank's my closest friend, the closest thing I have to a brother," Gore says. "He's a voice of reason and calm." This relationship is one area of Gore's life absolutely immune from polls and calculations. He always wanted Hunger at his side down the stretch. "It was on page 362A of the plan," Gore jokes, "paragraph three."

It is often said that Gore has few close friends, and many of those he does consider friends--Tom Downey, Roy Neel, Peter Knight and Jack Quinn--are Washington lobbyists or lawyers who, whether they seek it or not, stand to gain from their relationship with Gore. Hunger, like Tipper Gore, has only one loyalty. "There's no Frank Hunger agenda," says Jim Neal, the Watergate prosecutor, Gore lawyer and friend of both men. "When he gives advice it's his heartfelt belief, right or wrong." Adds Walter Dellinger, the former U.S. solicitor general: "Frank has absolutely no interest in gaining from his access."

Hunger, who at 64 is 12 years Gore's senior, met his late wife's brother 40 years ago. In the 16 years since Nancy Gore's death from lung cancer, Hunger, still a bachelor, has served Gore constantly. He has lived in the Gores' own private Virginia home for the seven years the Gores have lived at the Naval Observatory. He is a weekly fixture at the Gores' official residence, where he grows hot peppers and supplies beer for family cookouts.

"Uncle Frank," as he is known, goes to his nephew Albert's football games and had a role in Karenna Gore Schiff's wedding ceremony. He took Albert and Karenna on a trip to Europe in 1996, spends holidays and watches movies with the Gores, and jogs with the vice president. "I love his children as though they were my own," says Hunger, who is childless.

When Karenna was younger, Uncle Frank gave her sips of beer and let her stay up late. She later confided in Hunger her doubts about finding the right man before she met her husband, and he's the guy who "always tracks down a bottle of red wine" on the campaign trail. And he's leak-proof. "He will never betray my father's confidence, so it allows my father to bat ideas or brainstorm or hypothesize without it showing up in the papers," she says.

Hunger, whose parents and wife are dead and who isn't very close to his only brother, sees the Gores as his family. "When Frank lost Nancy, I think the best way to still be connected to her was through her family," says Jay Stein, an old friend who runs the Stein Mart national retail chain. "That's what motivates him. More than anything else, he's saying to himself, 'Wouldn't my wife be proud?' Every time Al would win an election it was bittersweet because Nancy wasn't there to see it."

He keeps photos of Karenna and Kristin at their high school graduations, wearing a white dress of Nancy's, on the shelves of his Washington law office amid dozens of photos of the Gores. "I see some of her in every one of them," Hunger says with a tear on his cheek.

Hunger doesn't share information about the vice president even with close friends. "He doesn't talk to me about Gore," says Stephen Thomas, Hunger's longtime law partner at the Lake Tindall law firm in Greenville, Miss., which Hunger left after 1992.

But Hunger is in on virtually every key Gore decision. He has advised Gore on top appointments to his campaign, combed through the line items in the campaign budget, recommended that Gore move his campaign to Tennessee, and recently urged Gore to soften his attacks on Bush. He normally avoids offering strategic advice--Gore's advisers were nonplused when he showed up for a recent political strategy session--saying he'd be "out of bounds" to do so.

But he doesn't hesitate to make occasional recommendations, with mixed results. He encouraged Gore to make a campaign issue of high gas prices, which worked out fairly well. But he also encouraged Gore to make his 1996 convention speech about Nancy's lung cancer death, which later came back to bite Gore. Still, Hunger sometimes is uncomfortable with this access to power. When Tony Coelho called Gore to say he was too ill to continue as campaign chairman, Hunger, who was sitting with Gore, decided to leave the room.

'Anything for Him'

Frank Watson Hunger was born in Winona, Miss., pop. 3,000, the son of the local dry-cleaning proprietor. Hunger worked in an auto factory and in a grocery store. The town was totally segregated, and Hunger knew he wanted to leave after he graduated with the 27 other students in his high school class. "We knew our lives probably were not going to be lived out in Winona," says Jane Dixon, a lifelong friend of Hunger's who is now an Episcopalian bishop in Washington. Hunger's older brother, S.H. Hunger Jr., still runs the dry-cleaning business with his children in Winona. "He didn't want to work--that's why he became a lawyer," S.H. Hunger jokes.

Gore is often accused of not knowing who he is, not being sure whether he grew up at St. Albans School for Boys or on a farm in Carthage, Tenn. For Hunger, there can be no doubt about his roots. He keeps a thick Mississippi drawl and brings back tomatoes from Greenville for people in his Washington office. When, in the Clinton-Gore administration, he became an assistant attorney general, he drove a Toyota pickup truck to his job at the Justice Department. When in town, he dines nightly at the Calvert Grill, a fried-chicken joint in Alexandria, where he socializes with mechanics, insurance agents and telephone linemen. He keeps a toy pig in his office, a remnant of a lawsuit on hog cholera. He hunts dove and duck on his friend Billy Percy's farm.

Still, Hunger shows an eccentric streak. He keeps an old Jaguar and a Beechcraft 36 airplane in Greenville. He sends his neckties to a dry cleaner in New York that unstitches them. On his 60th birthday, he jumped from a plane. "He has former roommates who are federal judges and U.S. senators on the one hand, and on the other hand good old boys whose Cadillacs have long horns on the hood," says Roy Campbell, a friend from Greenville. Indeed, Hunger has even been known to attend events for Republican Sen. Thad Cochran, a law school roommate.

But it is Gore who gets Hunger's fiercest devotion. "I'll do anything for him," he says. "I've got no closer or better friend." If Hunger has a fault in his relationship with Gore, it's that he's so devoted to his brother-in-law that he can't even approach objectivity. In Hunger's eyes, Gore can do no wrong.

Did Gore have it easy in Vietnam? "That galls me. Give me a break."

Has Gore switched positions on abortion? "That's nonsense!"

Was Gore raised to run for office? "That's B.S."

Is Gore stiff? "(Expletive)!"

Was Gore insincere in his '96 speech about his opposition to tobacco after Nancy's death? (The Gore farm continued to grow tobacco after her death.) "Jesus Christ--tobacco growing? Everybody in the world down there did . . . . He never thought about that more than flying to the moon. It's just nuts."

Son-in-Law and Son

Hunger, fresh from the University of Mississippi, met Nancy Gore in 1959, when he visited Jane Dixon at Vanderbilt before leaving for Taiwan to be an Air Force personnel officer. He still remembers Nancy Gore's outfit: plaid skirt, bobby socks, white blouse. "The most attractive woman I'd ever seen," he says.

After the Air Force, Hunger returned to Ole Miss for a year of law school, the year rioters clashed with the National Guard over the school's racial integration. Hunger also worked for the state's moderate former governor, J.P. Coleman, in his losing gubernatorial campaign against a segregationist. Disgusted, Hunger transferred to Duke Law School and then clerked for Coleman on the 5th Circuit Court of Appeals in New Orleans, which wrote landmark civil rights rulings. Throughout this time, Hunger dated Nancy Gore; they married on the Gore farm in 1966, and she followed him to Greenville.

Nancy Gore had been close to Sargent Shriver and helped to start the Peace Corps. She was a feisty and outspoken liberal, but when she moved to Mississippi, she assumed the traditional role of homemaker, doing charitable work on the side. "That sort of surprised me," says Jim Neal. Hunger and his bride were odd fits for Mississippi, but Greenville was an oasis, a town where Hodding Carter's Delta Democrat-Times was a beacon of civil rights.

Hunger's interests, though, often turned to Tennessee. He got to know the teenage Al Gore and visited with the young Al and Tipper on the farm in Carthage. He encouraged Gore to go to law school, and when Gore first ran for Congress, Hunger flew up on weekends to drop leaflets. When Nancy Hunger was diagnosed in 1982, the beginning of a two-year illness, Hunger took time off from his law firm and flew her to Nashville for treatments. Hunger spent many hours with Nancy's only sibling as she died.

"He loved Nancy as much as I did," says an emotional Hunger. "He treated me like a brother and his parents treated me like their child." When Ralph Thompson, a Hunger Air Force buddy and now a U.S. appellate judge, once dined with the senior Gores, Thompson remarked that they were lucky to have Hunger for a son-in-law. "Ralph," Pauline Gore replied, "Frank is our son."

Hunger piloted Gore around Tennessee in a single-engine plane for his 1984 Senate race, and he appears in Gore's swearing-in photo, dedicated "to the world's greatest brother-in-law." Hunger keeps that on his office wall, with one of the two men embracing as the 1992 election results were announced.

One Man's Trials

In Greenville, Hunger was a top trial lawyer, heading the 5th Circuit bar association and serving as the senior partner at Lake Tindall, which he had joined in the '60s. He tried hundreds of cases and specialized in defending corporations; he helped Honda battle liability from rollovers of its all-terrain vehicles, and he helped Shell and Ashland Oil defend their toxic liabilities.

When Gore asked Hunger to join his administration in 1993, Hunger took a job as head of the Justice Department's 700-lawyer civil division, where he worried that people would doubt his abilities because of his ties to Gore. "It was easy to underestimate Frank," says Dellinger. But Hunger brought in record money recoveries for the government in fraud lawsuits, reports Stuart Schiffer, Hunger's former deputy. Sen. Cochran, normally a critic of Clinton's Justice Department, said his friend "was a force that was desperately needed."

Throughout his ascent, though, Hunger has carried with him a palpable sorrow. When his law colleague Philip Bartz talked to him about Bartz's Labrador's death, "Frank couldn't talk about it--it got him choked up," Bartz says. Hunger keeps the 1972 Pontiac he and his wife used, even though it costs a fortune in upkeep. He keeps his Greenville home much as it was before she died, with pictures of the happy couple throughout.

Hunger also takes Nancy Gore's memory with him on her baby brother's campaign as he crisscrosses the country on little sleep. "I just know she would really want this," he says. "What success I've attained if any in life is in large measure from what she gave me as a person. She was always my champion and my best friend, the best thing that ever happened to me." With Nancy gone, the best Hunger can do now is repay the debt--to her brother. "I damn well am gonna be there for him," he says.