Source: Caroline Kennedy vetted for Japanese ambassador post By Jessica Yellin, CNN Chief White House Correspondent April 1, 2013 -- Updated 1628 GMT (0028 HKT) Caroline Kennedy attends Grand Central Terminal 100th Anniversary Celebration at Grand Central Terminal on February 1, 2013 in New York City. The daughter of JFK provided key support to President Obama in his 2008 campaign She is the best-known living member of one of America's most influential political families Washington (CNN) -- Caroline Kennedy has been asked to serve as the U.S. ambassador to Japan and is being vetted for the post, a Democrat familiar with the discussions told CNN on Monday. Kennedy, 55, the daughter of former President John F. Kennedy, was a top backer of President Barack Obama during both of his presidential campaigns and served as the co-chair of his vice presidential search committee in 2008. She's the only surviving member of JFK's family and has largely shunned the limelight and scrutiny associated with her famous last name. After publicly expressing interest in running for the U.S. Senate seat in New York vacated when Hillary Clinton became secretary of state in 2009, she ultimately decided against making a bid, citing "personal reasons." She made speeches at the 2008 and 2012 Democratic National Conventions, both times recalling her famous relatives -- in 2008, her speech served as a tribute to her uncle Sen. Ted Kennedy, and in 2012 she noted that "like my father's election in 1960, this is one of those elections where the future of our country is at stake." After receiving degrees at Harvard and Columbia, Kennedy served in a variety of roles at New York non-profits, including the John F. Kennedy Library and the American Ballet Theatre.