Ted Kennedy is jumping aboard the Obama bandwagon.

Senator Ted Kennedy, D-Mass., will endorse Barack Obama’s presidential bid on Monday in Washington, a source close to Kennedy tells ABC News.

The endorsement gives Obama a boost in the eyes of the Washington establishment, and comes after some prominent Democrats criticized Senator Hillary Clinton, D-N.Y., and former president Bill Clinton for their campaign tactics before Obama’s landslide victory in South Carolina.

Caroline Kennedy, the late President John F. Kennedy’s only daughter, announced her endorsement of Obama in an Op-Ed for the New York Times on Sunday.

And in an exclusive “This Week” interview, Obama hinted that the senior senator from Massachusetts might be next.

“I’ll let Ted Kennedy speak for himself. And nobody does it better. But obviously, any of the Democratic candidates would love to have Ted Kennedy’s support. And we have certainly actively sought it,” Obama said. “I will let him make his announcement and his decision when he decides it’s appropriate.”

UPDATE at 1/27/08 12:46:55 pm:

Yes, even Jonathan Chait and the Los Angeles Times are souring on the Clinton dynasty.