John Winthrop Sears, whose name evokes the same knowing nods among longtime residents of this city as a Rockefeller might in New York, lives on Beacon Hill, amid a clutter of books and heirlooms in a 430-square-foot apartment that he says his great-great-grandfather would have considered a "cloak closet."

Just down the street, where his neighborhood meets the Boston Common and Public Garden, stands the private Somerset Club, a stately, stone edifice that was once the Sears Mansion.

"Most of the old Yankee families . . . are gonzo," Sears, a 73-year-old retired Republican politician who once ran for governor, says, thumbing, with no hint of irony, through a book about the fall of the Roman Empire. "A new meritocracy has arisen around us, a mix of kids just out of college, young professionals, and people with lots and lots of bucks."

Beacon Hill was long the de facto capital of Boston's blueblood establishment -- Mayflower types with names like Hancock and Copley and some more recently arrived aristocrats. The neighborhood lost some of its luster in the 1950s and 1960s when many of its residents began migrating to the suburbs. But as downtown Boston revitalized in recent decades, Beacon Hill became the hot corner of the real estate market and rich outsiders like Sen. John F. Kerry renovated dilapidated buildings into elegant homes. Meanwhile some larger buildings were divided into hundreds of pricey shoebox-size flats and others were converted into subsidized housing.

Today, the Hill, as locals refer to it, packs 10,000 residents into a square-mile rabbit warren of gaslit streets lined with Georgetown-style townhouses. Kerry, the Democratic presidential candidate, represents both the old Beacon Hill and the new. Like Sears, he is a descendant of John Winthrop, the 17th-century founder of the Massachusetts Bay Colony. But he moved in from the suburb of Brookline only seven years ago.

"Most people don't know them that well yet," says Sears of Kerry and his wife, Teresa Heinz Kerry. "They're mostly focused on Washington and other places where they own homes, and lately they've been a little busy."

From the Kennedy compound on Cape Cod to George W. Bush's Texas ranch, the homes of U.S. presidential candidates play a prominent role in the public perception of who they are. The thousands of journalists and delegates expected to stroll past Kerry's three-story home during the Democratic National Convention -- to be held here at the end of the month -- will encounter a neighborhood no longer bound by old stereotypes. Stodginess, residents say, is a fading undercurrent in a community now defined as much by its quirkiness as anything else.

"I think it's the water," jokes Henry Lee, head of the Friends of the Public Garden, who recently sold the Beacon Hill home he bought for $25,000 in 1959 for $3.3 million. "After 10 years, people here get a little strange."

Living alongside notables like former General Electric chairman John F. Welch and best-selling medical novelist Robin Cook -- who both own Beacon Hill homes -- is a deep-voiced "Avon lady" who goes by the name of Rose and peddles beauty products and homemade jewelry. Peter the trash-picker peruses his neighbors' rubbish daily for antiques. There are happily married couples who live across the street from each other in separate apartments and billionaires who drive beat-up jalopies.

"Every block seems to have its share of interesting folks," says Karen Cord Taylor, editor of the weekly Beacon Hill Times, who has lived in the neighborhood for 35 years. "One of the defining characteristics of this place is eccentricity, and the tolerance for people who in other places might be considered a little bit bizarre."

Settled in colonial times, the Hill first achieved prominence with the completion of the gold-domed statehouse at its crest in 1798. In the 19th century, a divide emerged between the aristocratic southern slope, where the mansion built by Sears's great-great-grandfather, David Sears, stands, and the more bohemian north side, which was home to working-class whites and a majority of Boston's small African American community, as well as the nation's first public school for blacks. The north slope soon became known as a literary enclave and a hotbed of the abolitionist movement, with residents like novelist Harriet Beecher Stowe.

The term Boston Brahmin was popularized by Beacon Hill resident Oliver Wendell Holmes, a physician, writer and father of the Supreme Court justice. But the renowned haughtiness of that culture is perhaps best described in the derisive 1910 poem "A Boston Toast," by John Collins Bossidy, which reads:

And this is good old Boston,

The home of the bean and the cod,

Where the Lowells talk only to Cabots

And the Cabots talk only to God.

The Hill is now one of Boston's whitest neighborhoods -- minorities make up some 15 percent of the population here, compared with more than 50 percent in the city overall, according to 2000 census figures.

Still, residents say it exhibits diversity in other ways. "You get a house painter sitting next to a guy who owns the biggest construction company in Boston, political types and rowdy kids," says bartender James McCarthy, 37, who pulls pints at the Sevens, a Beacon Hill institution since the 1930s.

Three years ago when Karen Fabbri, 30, opened Moxie, a store that sells designer leather shoes and handbags, on Charles Street, the Hill's main commercial thoroughfare, virtually every other store was an antique shop. Now, she said, high-end restaurateurs and her fellow fashionistas are making their way in.

"It's getting trendier, hipper and younger," Fabbri says.

For decades, the Hill was a majority Republican district. While George W. Bush's aunt has a home here and several neighbors have written $2,000 checks for the Bush campaign, the neighborhood is now mostly Democratic. But residents seem as concerned with neighborhood affairs like historic preservation -- and the Hill's dozens of civic organizations -- as national politics. A summer competition to create the best window boxes draws hundreds of entrants, and the city's decision to change a one-way street last year had residents taking to the streets, counting car traffic to gather evidence against the plan.

"It's such a small world that when things happen it spreads like wildfire," Taylor says. "And we have certainly had our share of strange events."

People chuckled all over Boston when the Big Dig, the city's famously overdue and over-budget highway construction project, unearthed a horde of rodents that made a new home on the Hill.

And tongues wagged in June, when former governor William F. Weld (R), a descendant of one of Boston's oldest families, gave the homily in the same-sex wedding of longtime aide and fellow Brahmin Mitchell Adams. The reception was held in the Somerset Club. Legend has it that city firemen responding to a blaze at the club were once told they had to use the servants' entrance.

These days, much of the scuttlebutt is focused on the Hill dweller running for president.

For the most part, neighbors say, Kerry -- who, with his wife, also owns homes in Georgetown, Sun Valley, Idaho, on Nantucket and outside Pittsburgh -- has kept a relatively low profile since 1997, when he paid $2.2 million for a red-brick 18th-century townhouse on Louisburg Square that was once an Episcopal convent. He caused a minor flap a few years ago by paying for a fire hydrant to be moved around the corner, to provide for more parking. During the Democratic primaries, he boosted his dwindling campaign coffers by mortgaging the home for $6.4 million. The house, now assessed at $6.9 million, has five stories, six fireplaces and an elevator.

Since March, conspicuous Secret Service agents have patrolled the small green bounded by two private lanes.

"We want this to be a positive experience," agent John Rodrigues told a March gathering of Kerry's neighbors, reported the Beacon Hill Times, which has chronicled their presence closely. "I've protected seven U.S. presidents and I've never seen the Secret Service devalue a neighborhood."

Agents generated complaints by running the engines of their black Chevrolet Suburbans all night and occasionally blocking access to adjacent streets. But they also earned praise for making residents feel safer, and even stopped a man from urinating on a car.

"We aired our concerns but for the most part we are taking all the craziness in stride," says the novelist Cook, resting on his stoop across the square from Kerry's home.

Some neighbors are not looking forward to the increased foot traffic the convention will bring. "My God, it's gonna be a gawker's paradise around here," says longtime resident Walter "Bud" Patten.

Others are trying to cash in by renting their homes during convention week.

"Stay in a Multi Million Dollar Home -- THREE DOORS AWAY FROM JOHN KERRY!!!" screams one listing on an apartment Web site.

Kim Kolloff, who says she lives four doors from Kerry and has a roof deck overlooking his home, is hoping to rent the six-story house she moved into a year ago for up to $50,000, including valet parking and daily maid service. "So far we've only had one offer and it was a real lowball," she says. "If you're coming into Boston, seriously, where else would you rather be?"

"A new meritocracy" has changed Beacon Hill, says resident John Winthrop Sears, above. The neighborhood also must cope with a Secret Service presence at candidate John F. Kerry's home.Beacon Hill resident Oliver Wendell Holmes popularized the term "Boston Brahmin." The character of Beacon Hill varies from the exclusive Somerset Club, below, to humble but charming rowhouses, left. Karen Cord Taylor, below left, editor of the neighborhood newspaper, says Beacon Hill has "tolerance for people who in other places might be considered a little bit bizarre."