Edward M. Kennedy’s death in 2009 and his son Patrick’s retirement from Congress prompted speculation that, with no other family member left in a high profile public office, the Kennedy legacy had run its course. But 31-year-old Joseph P. Kennedy III may prove them wrong.
Kennedy, son of the former congressman and grandson of Robert F. Kennedy, has taken the first official steps toward launching a congressional run to replace retiring Democrat Barney Frank.
He has created an exploratory committee and announced his resignation from his job as a prosecutor in the Middlesex district attorney’s office.
Senior Democratic sources who have talked to Kennedy said that he has already concluded that he will run for the Democratic nomination to represent the redrawn Newton and Brookline-based district that extends to parts of Fall River, though Kennedy said he will make a decision about entering the race in the coming weeks.
His aides said Kennedy would not submit to any interviews until he leaves the district attorney’s office two weeks from now.
In a statement, he said, “My decision to look seriously at elected office is grounded in a deep commitment to public service and my experience - both my own and that of my family - in finding just, practical, and bipartisan solutions to difficult challenges.’’
His father, Joseph P. Kennedy II, declined to comment.
With his name and family legacy, Kennedy, a Harvard Law School graduate and former Peace Corps volunteer, would enter the race as the prohibitive favorite. One poll taken by a potential candidate showed him with a huge lead over possible Democratic rivals.
He would also be able to depend on his family’s extensive fund-raising base and the lingering nostalgia among voters for the Kennedy family, allowing him to put together what veteran political observers say would be a formidable campaign.
But his credentials and experience would undoubtedly be called into question by opponents, much as they were decades ago for his great uncles: future President Kennedy and Edward M. Kennedy when he first ran for the Senate.
Critics will charge that he is riding the coattails of the family name and parachuting into a congressional district where he has not lived.
His supporters point to his academic credentials, both at Harvard and as an undergraduate at Stanford University, his volunteer work in the Dominican Republic, and his more than two years as a prosecutor in two counties.
Kennedy is the first in the fourth generation of Kennedys to thrust himself into electoral politics. That road to power and influence in Massachusetts and Washington was created by Kennedy’s great-grandfather and namesake, Joseph P. Kennedy Sr., a wealthy, self-made businessman who was US ambassador to Britain in the Roosevelt administration.
Doris Kearns Goodwin, the historian whose book, “The Fitzgerald and the Kennedys,’’ chronicled the family history, said Joseph Kennedy III’s run for Congress puts to rest the speculation that the family’s involvement in state and national politics is over.
“While the death of Ted Kennedy marked the end of an era, we are now seeing the emergence of a fourth generation that is following the family’s heritage of politics and public service,’’ she said. “It was premature to say the Kennedy era had come to the end.’’
But Laurence Leamer, who has written three books about the Kennedys, said the mythology around the family has all but disappeared, citing the 2002 defeats in Maryland of Mark Shriver in a congressional primary and of Kathleen Kennedy Townsend in a race for governor.
“The magic was gone then, so I think he deserves more than to be touted as the heir to this tradition,’’ Leamer said. “It was getting kind of unseemly.’’
Kennedy’s probable entrance into the race is likely to thin out the Democratic field, observers say. Political strategist Mary Anne Marsh compared it to the impact Elizabeth Warren had on the US Senate race when she declared this fall, prompting several leading candidates to quit.
“He may not clear the field entirely, but it will significantly shape the field,’’ Marsh said.
Former US Senate candidate Alan Khazei said yesterday that he had decided several days ago not to pursue the Fourth Congressional District seat, as did Deborah B. Goldberg of Brookline, an unsuccessful candidate for lieutenant governor in 2006. Another possible candidate - Michael P. Ross, a Boston city councilor - said he has not yet made a decision.
On the Republican side, Elizabeth Childs of Brookline has formally declared she will run, while former Frank opponent Sean Bielat has signaled that he is considering a run.
Raised in Brighton and Cambridge, Kennedy is currently living at his mother’s home in Cambridge, but plans to move to a Newton apartment Feb. 1, an aide said yesterday.
Once he leaves his job, he said he will “begin to reach out to the people of the Fourth District, in order to hear directly from them about the challenges they are facing and their ideas on how we can restore fairness to our system.’’
Kennedy’s father, elected to Congress in 1986 in a Boston-based district, was often cited as the future political leader of the family. He began running for governor in 1998, but bailed out a year before the election because of news reports about his brother Michael’s relationship with his children’s baby-sitter.
The younger Kennedy’s parents divorced in 1991. The split, while amicable, swerved into a nasty public dispute several years later when his father sought an annulment. His mother wrote a book about the battle, detailing some of their personal arguments and adding considerable bitterness to the separation.
Joseph Kennedy III’s interest in politics has been evident since he graduated from law school. He has been moving in state Democratic circles and attending party events since he emerged on the scene in 2006 when he co-chaired Edward M. Kennedy’s last Senate campaign with his twin brother.
He had taken a serious look at running for congress in the South Shore district when veteran incumbent Democrat William D. Delahunt retired last year, ultimately deciding against it. At the time, he was working as a prosecutor at the Barnstable district attorney’s office, a post he left in September to join the Middlesex office.
A Kennedy candidacy will create another political hurdle for Republican hopes of capturing a congressional seat.
Some conservatives still believe they have a strong shot. “Why a dyed-in-the-wool liberal Kennedy would want to run for a seat that Barney Frank left because he couldn’t win is beyond me,’’ said Christine Morabito, president of the Greater Boston Tea Party.
But Charley Manning, a Republican consultant who was the chief consultant to Mitt Romney’s 1994 challenge to Senator Kennedy, said he never believed that the Kennedy family would disappear from the state political scene.
“I always thought we would have another Kennedy running in Massachusetts,’’ Manning said. “I hear he is pretty good kid. They say he is much more like his mother than his father,’’ he added of Joseph Kennedy II’s sometimes pugnacious public image.
Indeed, the younger Kennedy has made a strong impression, among his colleagues and increasingly in the political world. “He combines special intellectual talents with thoughtfulness,’’ said former congressman Martin T. Meehan.
Gerard T. Leone, Jr., the Middlesex district attorney, said Kennedy’s record will stand up well, despite only having tried two cases since joining the office this fall. “I told him if things don’t work out, he would very welcome back here,’’ Leone said.
Noah Bierman of the Globe staff contributed to this report. Frank Phillips can be reached at email@example.com.