BOSTON — With the family shut out of the White House and Congress for the first time in more than a half-century, a scion of the Kennedy clan on Thursday took the first steps toward a run for retiring Rep. Barney Frank's Fourth District seat in Massachusetts.
Confirming widespread speculation here, Joseph Kennedy III, the 31-year-old son of former Rep. Joseph P. Kennedy II and a grandson of the late Robert F. Kennedy, said Thursday he is forming an exploratory committee and is resigning his prosecutor's job in Middlesex County outside Boston.
Mr. Kennedy said he would make a final decision about whether to run in the coming weeks, but Democratic officials fully expect he will be a candidate. The formation of an exploratory committee will allow Mr. Kennedy to begin raising money for the race.
"I look forward to this new challenge, and to meeting people across the district in the weeks ahead," he said in a statement.
The Kennedy family has seen its influence in Washington fade in recent years as its younger generations have largely shunned public office.
The death of Sen. Edward Kennedy of Massachusetts in 2009 left a void for the family. The retirement of his son, Rep. Patrick Kennedy of Rhode Island, last year marked the first time in 63 years that there was not a Kennedy serving in elected office in Washington.
Several candidates in both parties are considering jumping into the race, including Republican Sean Bielat, who lost to Mr. Frank by 54 percent to 43 percent in 2010. One Republican, Brookline resident Elizabeth Childs, has officially announced for the seat and Democrat Herb Robinson, a software engineer from Newton who was briefly a candidate for U.S. Senate, also plans to run.
John Walsh, chairman of the Massachusetts Democratic Party, said he was excited about the prospect of Mr. Kennedy entering the race and holding the seat for the party.
"Because of the quality of our candidates, we are confident the Democratic candidate will be the better choice to match the values and needs of the voters of the 4th District," he said in a statement
The district, which currently snakes from the upscale Boston suburbs of Newton and Brookline to the cities of New Bedford and Fall River in southeastern Massachusetts, has been somewhat reshaped under a new congressional district map, a factor cited by Mr. Frank in his decision to retire after more than three decades in the House. New Bedford, a prominent fishing port and Frank political stronghold, has been shifted to a new district that includes Cape Cod.
Mr. Kennedy is a graduate of Stanford University, where he studied management science and engineering and was co-captain of the lacrosse team, and of Harvard Law School, where he served as technical editor of the Harvard Human Rights Journal.
He served in the Peace Corps in the Dominican Republic from 2004 through 2006.
• Andrew Miga reported from Washington.