WASHINGTON -- Caroline Kennedy is beginning to show a real enthusiasm for the family business.

When the daughter of John F. Kennedy was named to Sen. Barack Obama's vice-presidential search committee, many political observers saw the move as mere political window dressing. But Ms. Kennedy has emerged as a crucial member of the vetting team, and is proving a major draw on the campaign trail as well.

Ms. Kennedy and former Justice Department official Eric Holder, co-heads of the search committee, recently completed extensive meetings with Democratic lawmakers and others to discuss possible vice-presidential candidates. They have helped Sen. Obama to winnow the list of potential running mates to about a half dozen, campaign officials say. (Please see related article on Page 10.)

Ms. Kennedy and her team are no longer seeking input from outsiders; they are now working closely with Sen. Obama as he moves toward making his choice. And they don't discuss the selection process on the phone, because Sen. Obama is "never alone, even in the car, now," says one campaign aide.

The committee has tried hard to keep its deliberations secret. Ms. Kennedy declined to be interviewed. Many of the people with whom she's met won't talk about the substance of the conversations.

When the search process draws to a close, Ms. Kennedy will continue working on Sen. Obama's behalf, campaign officials say. Her increasing visibility in the campaign has sparked speculation that Ms. Kennedy, who strived for years to avoid the limelight, may have a political future of her own.

When she appears on the campaign trail, some people show up clutching books by or about Ms. Kennedy, her mother or her father, which they ask her to autograph. Earlier this year, when she accompanied Michelle Obama to a campaign event in Jeffersonville, Ind., the crowd closed in on Ms. Kennedy. She shook hands and posed for pictures.

"I got so close to Caroline Kennedy, I couldn't believe it," says Jean Wilson, a 66-year-old pastor who was there. "I told her how much I loved her father. She did so well, she could become a politician herself."

Some political operatives see Sen. Obama's embrace of Ms. Kennedy as a calculated bid to win more votes. It's "an effort to build a bridge to the Kennedy aura and legacy," says Kevin Madden, a Republican strategist who isn't affiliated with Sen. John McCain's campaign. "It's not that ingenious a political move to want Caroline Kennedy," he says. Sen. McCain reached out to Nancy Reagan, he notes. "To reach more voters, the Democrats have Kennedy, and we have Reagan."

Although Ms. Kennedy has endured the glare of public attention from the time she was a toddler, she has always tried to stay out of the public eye. Following the assassination of her father, her mother moved the family to New York, where Caroline Kennedy has lived, for the most part, ever since. She married designer Edwin Schlossberg and raised three children, now age 15 to 19. She has written books ranging from an examination of the constitutional right of privacy to a compilation of her mother's favorite poetry. She rarely agrees to be interviewed, and can walk the streets of her Upper East Side neighborhood without drawing attention.

In 2002, Joel Klein, chancellor of New York City's school system, asked Ms. Kennedy to develop a new initiative that would form strategic partnerships with the private sector and raise money. Mr. Klein's wife, Nicole Seligman, a Sony Corp. executive vice president, had been Ms. Kennedy's college friend and bridesmaid.

"With her children getting older, Caroline was thinking of engaging in more active public service," says Mr. Klein. Ms. Kennedy took on the task, and until 2004, worked from a desk not far from Mr. Klein's in the "bullpen" of the school system's headquarters. "Lurking beneath her public shyness is a person with a great wit who works hard," says Mr. Klein.

When the presidential race got rolling last year, Ms. Kennedy began taking her children to events -- for both Sen. Obama and Sen. Hillary Clinton. Ms. Kennedy and Sen. Clinton were on friendly terms, according to one Clinton campaign aide. Ms. Kennedy wasn't expected to weigh in during the primary contests.

But her children expressed a strong preference for Sen. Obama, which had an impact, according to several of her friends. Her elder daughter was in college, her second daughter was in her last year of high school, and her son was a few years younger. "The timing was perfect for her to get more involved," says one of those friends. "And her children inspired her."

In November, Ms. Kennedy celebrated her 50th birthday. At a private party in the New York Public Library, singer Neil Diamond sang "Sweet Caroline," via satellite, and revealed that the song had been inspired by a photograph of Ms. Kennedy as a child. She appeared on the cover of the magazine put out by AARP, the lobbying group for people 50 and older. "Turning 50 made her ask herself, 'How can I do more?' " says another of Ms. Kennedy's friends.

Inside the Clinton campaign, advisers were assigned to seek political endorsements from key figures, including Sen. Edward Kennedy. "Because Hillary has a personal relationship with Caroline, no one was given the responsibility to check in with Caroline," one adviser says.

After former president Bill Clinton attacked Sen. Obama, calling his campaign a "fairy tale," word got out that some leading Democrats, including certain Kennedys, were so angry they might endorse the Illinois senator. Chelsea Clinton -- not her mother -- called Ms. Kennedy as one "first daughter to another," says one Clinton adviser. Her plea: stay neutral.

Ms. Kennedy didn't. She wrote an editorial for the New York Times, which ran on Jan. 27 under the headline "A President Like My Father." The next day, Ms. Kennedy and her uncle, Sen. Kennedy, appeared with Sen. Obama at a packed Washington rally. She later made a television ad for Sen. Obama.

Since then, Sen. Obama and Ms. Kennedy have developed a friendship, chatting and emailing one another frequently, according to Valerie Jarrett, a friend of Sen. Obama's.

In the spring, Ms. Kennedy and Mrs. Obama traveled together in a minivan to southern Indiana to campaign. At a rally at a 4-H club, they stood together at a rope line, where many in the crowd waited to greet Ms. Kennedy.

As they rode to the next event, they talked about their children. Ms. Kennedy said she planned to take her middle child to Italy on vacation after her high-school graduation, according to someone familiar with the conversation. Mrs. Obama said she wouldn't let campaign events cause her to miss her daughter's ballet recitals, this person says. Ms. Kennedy offered ideas for keeping their two girls' lives as "normal" as possible.

Mrs. Obama said in a written statement that Ms. Kennedy's "friendship and support have been immeasurable for Barack and me."

In June, Sen. Obama asked Ms. Kennedy to be one of three members of his vice-presidential search committee. Joining her on the committee was Mr. Holder, the former Justice Department official, and James Johnson, the former head of housing-finance giant Fannie Mae.

The group's task was to bat around names with Sen. Obama; to meet with lawmakers and others to seek feedback on candidates and to get additional suggestions; and to supervise a group of lawyers who would thoroughly comb the public record for information about the candidates.

Messrs. Holder and Johnson handled the initial round of meetings, because Ms. Kennedy was out of the country with her daughter. That fostered the notion that Ms. Kennedy wasn't included to do any heavy lifting, just to lend her name to the effort.

"We couldn't criticize Obama for taking on the Kennedy aura," notes one adviser to Sen. McCain, "because with her and Teddy's endorsement, it was completely legitimate for him to claim the family connection."

In mid-June, Mr. Johnson stepped down from the committee after The Wall Street Journal disclosed he had received loans from Countrywide Financial Corp., a major subprime lender, which sparked criticism. Obama campaign officials began brainstorming over a replacement.

When Ms. Kennedy returned to the U.S., she huddled with Mr. Holder in Washington to go over the material that had been gathered and to discuss what was needed next. They set up a "war room" to review the material flowing in from the lawyers, who were going through the voting records, newspaper clips and other material, then banging out reports on each candidate.

Soon the Obama campaign decided that another vetter wasn't necessary. "That Jim Johnson wasn't replaced is a strong sign of the confidence in Caroline," says one campaign adviser. "She and Eric [Holder] are fundamentally co-equals."

Ms. Kennedy began making the rounds on Capitol Hill, speaking with leading Democrats, especially women, and with various interest groups. After reviewing several names with Rep. Carolyn Cheeks Kilpatrick, chairman of the Congressional Black Caucus, Ms. Kennedy asked, "Is there anyone else you recommend?"

Sen. Debbie Stabenow of Michigan, an important swing state, also met with her. "Caroline was thoughtful, asked questions and took notes," she recalls. Sen. Barbara Mikulski of Maryland, who met with her too, says Ms. Kennedy had "a personable way that elicits information very well."

Neither the two senators nor Rep. Kilpatrick will comment on the names that were discussed.

Ms. Kennedy met for one-and-a-half hours with Rep. Joe Baca, chairman of the Congressional Hispanic Caucus. She inquired about specific candidates. "I looked at Caroline, eye-to-eye, and asked if my comments would stay confidential, except to Sen. Obama," Rep. Baca recalls.

"What you say here will not leave this room," Rep. Baca recalls her responding. Before she left, Ms. Kennedy gave the congressman her private phone number.

As she moved about Washington, Ms. Kennedy tried to steer clear of the press. She slipped through the garage of the Democratic National Committee to attend meetings there with lawmakers. On another occasion, Ms. Kennedy and Mr. Holder left the building through a back door to bypass camera crews and TV trucks waiting for Sen. Obama to leave a separate meeting.

Once Sen. Obama narrowed the list of potential running mates, the vetting process got more intensive, with the committee digging into more personal information such as tax returns. Sen. Christopher Dodd of Connecticut, one of the names on the list, said recently: "There's been some inquiries, yeah. They ask for a lot of stuff. I'll leave it there."

Some Democrats speculate that if Sen. Obama wins, he might name Ms. Kennedy, who has a law degree, to a high-level post in his administration.

In the meantime, Ms. Kennedy appears to be growing more comfortable with being a public figure. One day earlier this month, she met privately with Sen. Obama to discuss potential running mates. Then she accompanied Sen. Kennedy, who is recovering from brain surgery and cancer treatment, from his home to Capitol Hill, where he cast a decisive vote on a Medicare bill.

Finally, she flew with Senators Obama and Clinton to New York, where the three appeared at Manhattan fund-raisers. At one small gathering, as big contributors lined up to get their photos taken with Sen. Obama, Ms. Kennedy worked the room.

"This Caroline wasn't the ill-at-ease, very private woman I've met before," says one attendee. "She was an outgoing, work-the-rope-line political Kennedy."