Joseph P. Kennedy III is mulling a bid for Congress should Rep. William Delahunt (D-Mass.) choose to retire, the Boston Globe reported Saturday.

The 29-year-old Kennedy is the son of former Rep. Joseph P. Kennedy II (D-Mass.) and the grandson of Robert F. Kennedy and serves as an assistant district attorney on Cape Cod. The Globe cited unnamed Democratic sources.

Delahunt, who is serving his seventh term in Congress, has said publicly that he is considering retirement.

Should Kennedy run and win in 2010, he would continue the family's long-running streak in Congress. If he or another member of the family does not, the retirement of Rep. Patrick Kennedy (D-R.I.) will mean that Congress will be without one of the clan for the first time since 1962, when Sen. Edward Kennedy (D-Mass.) was first elected.

Here is more from the Globe:

The sources say that Kennedy, a 29-year-old assistant district attorney on the Cape considered by many to be the most promising member of his generation to extend the family’s political legacy, is not close to making any decisions and will not speak publicly until Delahunt announces whether he will seek another term. The discussions are taking place very privately among Kennedy family confidants.

As Delahunt ponders his future and Democratic hopefuls eye a bid for his seat, Kennedy’s potential candidacy is weighing heavily on the field that is starting to take shape.

“If he runs, he is immediately the front-runner,’’ said state Senator Robert O’Leary, Democrat of Barnstable, who said he would run for the seat if Delahunt retires. “From my perspective if Kennedy enters the race, it obviously changes the dynamic and makes it more difficult. But it would not change my decision.’’

One potential hurdle, however, is the political climate in the state, and especially in that district, which went heavily for Republican Scott Brown in last month’s Senate election. If Kennedy were to run and win his party’s nomination, he could risk become a lightning rod for the newly energized conservatives from around the country who poured millions of dollars into Brown’s coffers. With no member of the family ever losing an election in Massachusetts, he would be putting the Kennedy legacy on the line.