Democratic Sen. Paul Sarbanes (search) of Maryland on Friday announced that he plans to retire from his near 30-year Senate career at the end of his term.

The liberal lawmaker will be the longest serving senator in his state's history when he retires next year instead of seeking a sixth term.

"It was not my ambition to stay there until they carried me out," Sarbanes said during an afternoon news conference at his Baltimore office. "It was just the right time. We think we've served long and well and honorably and we're very comfortable with this decision."

Sarbanes, 72, would become the second Democratic incumbent to retire rather than run again. Among Republicans, Senate Majority Leader Bill Frist (search) of Tennessee has long indicated he does not plan to seek a new term.

"I am deeply grateful to the people of Maryland, who have honored me with the privilege of representing them in elected public office for nearly forty years," Sarbanes said. "Throughout my years in public service I have always sought to provide the people of Maryland with dedicated, independent representation, based upon intelligence and integrity: representation that gives people confidence that elected officials are there to serve the public interest."

He thanked his Greek immigrant parents for teaching him the meaning of a democratic society and "the potential it offers to move up the ladder of opportunity on the basis of ability, hard work and conviction." He also thanked the Salisbury, Md., community where he grew up, and the city of Baltimore, where he and his family have lived and worked since 1960.

"My nearly 36 years in the Congress have been challenging and fascinating and it is a source of tremendous satisfaction to travel the state and see so many improvements in every region that I have played a role in bringing about," he said.

Sarbanes was first elected to the Senate in 1976, after a career in the House that included a seat on the Judiciary Committee during the Watergate impeachment hearings involving former President Richard Nixon.

Sarbanes' principal area of interest in the Senate has been the Banking Committee, where he has served as chairman or senior Democratic member for several years.

His is a reliably liberal vote on social and economic issues. This week, for example, he was one of 25 Democrats to oppose legislation to make it harder for consumers to shed debts through bankruptcy.

He vowed that, for the next 22 months of his term, he will work to oppose what he called "the tragic and misguided policies of this administration, especially the current radical attempt to undermine the Social Security system."

"You can be certain I will continue to do my very best to represent this State and all its people," he added.

Sarbanes said he made the announcement early to give other Democratic candidates a chance to start their campaigns. He declined to speculate on who would run for his seat, but said he expected a Democrat would win.

"We've a number of very able Democrats... I'm confident that one of them will be elected to the United States Senate in 2006 and I will do everything I can to bring around that result," he said.

Other congressional lawmakers said Sarbanes will be sorely missed.

"The decision by my close friend and colleague Paul Sarbanes to not seek re-election to a sixth term in the United States Senate will deprive the State of Maryland and the Congress of one of the most thoughtful, intelligent and committed public servants in our nation's history," House Democratic Whip Steny Hoyer of Maryland said in a statement, calling Sarbanes an "intellectual giant."

"He ranks among 'the best and the brightest,' who continually enriched our State and our nation over the last four decades with his leadership, wisdom and integrity. His record and career in public office ought to be emulated by all who wish to serve."

Another one of Sarbanes' Maryland colleagues, Democratic Rep. Chris Van Hollen, said the senior senator "always put conscience over politics" and that he was, to Van Hollen, "a model of how a public official can serve our community and country."

Added: Sen. Patrick Leahy, D-Vt.: "Paul Sarbanes is one of the Senate's finest. His decency, his intellect and his courage have been a credit to the Senate, and when he leaves, he will be missed by Democrats and Republicans alike."

Among Democrats mentioned as Sarbanes' possible replacement is former NAACP President Kweisi Mfume (search), who served five terms in the House before heading the civil rights organization.

While Sen. Mark Dayton's retirement triggered a scramble in Minnesota, Democrats have an inherent advantage in any Senate race in Maryland. In general, the state votes Democratic, having supported John Kerry over President Bush last fall.

For Maryland politicians, his decision would mark a rare event — an open Senate seat. The state's other senator, Sen. Barbara Mikulski (search), was first elected in 1986.

A retirement could also have repercussions in another high-profile race in Maryland next year. Republican Gov. Robert Ehrlich (search) is expected to seek re-election, and several Democratic challengers have begun maneuvering for the nomination to oppose him.

The Associated Press contributed to this report.