The decisions by Democratic Sens. Patrick J. Leahy of Vermont and Tom Harkin of Iowa to forgo taking over the Appropriations Committee in favor of keeping their current committee gavels could be a sign that the once-vaunted panel is losing its clout.

Both senators earlier this week waived their seniority on the panel, allowing the third-ranking Democrat on the committee — Sen. Barbara A. Mikulski, D-Md. — to take over after the death Monday of Appropriations Chairman Daniel K. Inouye, D-Hawaii.

The unusual situation is evidence to some Hill watchers that the spending panel’s stature is waning — given the recent political focus on cutting spending, the now-routine inability of lawmakers to fund the government by the statutory deadline of Oct. 1 each year and the moratorium on earmarks that Republicans have successfully imposed on Congress.

“Budget politics now dominate, but budget politics are driven by party politics and led by party leaders and the president,” said Steven S. Smith, a political science professor at Washington University in St. Louis. “Appropriators play a supporting, not a leading, role in that movie.”

Harkin, who is chairman of the Health, Education, Labor and Pensions Committee and the Appropriations Subcommittee on Labor, Health and Human Services and Education, said he has been frustrated by the inability to move his spending bill in recent years. That measure has been particularly hamstrung because of a disagreement with the Republican-led House over funding for the 2010 health care overhaul.

Harkin said the decision to take a pass on the post, traditionally viewed as more powerful than the HELP Committee, had much to do with his life’s work.

“I just had to think about who I am and where I am,” the Iowan said in a brief interview.

“I’m 73. I’ve been here a long time, and I’m at that point in my life where I don’t feel I have to do what others want me to do or expect me to do,” Harkin said. “I want to do what I love, and I love my committee. I love the issues we deal with, and I’m still on approps.”

He expressed optimism that Mikulski will be able to restore some semblance of regular order to the panel’s workings.

“I know Barbara Mikulski, and I know one thing. She is determined, and she’s a great leader, and if there is one person that could get the Appropriations Committee back up and functioning as it should, it’s Barbara Mikulski,” Harkin said.

Former Sen. Byron L. Dorgan, D-N.D., who served as chairman of the Energy and Water subcommittee, said the panel remains important, but he pointed to the difficulty in moving spending bills through the Senate and getting to conference committees where the panel leaders can actually make the decisions. The full Senate considered not one of the 12 annual spending bills this year.

“I don’t think there’s much question that the ability of the committees to have the final word on appropriations has diminished some,” Dorgan said, pointing to the number of decisions made at the leadership level on omnibus bills and stopgap continuing resolutions.

Defenders of the panel argue that its power is relatively strong, given its constitutionally provided power of the purse — even if it has been hindered by procedural obstruction in the Senate.

“I think all of Congress has lost its allure and stature,” said former House Appropriations Chairman David R. Obey, D-Wis. But he said, “In the end, it’s the appropriators that lay out specific action on programs.”

“I think the rumors of the committee’s demise are overblown,” said John Scofield, the former communications director for the House panel under Rep. Jerry Lewis, R-Calif. “It’s still the committee that writes the bills, late or whatever.”

Scofield, who co-founded Shockey Scofield Solutions, said the committee also remains a powerful and important check to the executive branch on a host of issues.

Obey agreed that the panel has lost some of its luster as a result of minority obstruction in the Senate.

“Its not very enjoyable to work your butt off [on a bill], knowing this sucker is not going to see the light of day because of obstruction,” Obey said.

Dorgan, Obey and Scofield also attributed Leahy and Harkin’s move to their particular circumstances — both are already in powerful posts that are expected to have jam-packed agendas next year.

As chairman of the Judiciary Committee, Leahy will control much of the way the Senate deals with some of the president’s top priorities, including immigration, gun control and possibly at least one vacancy on the Supreme Court. He is also expected to be chairman of the Defense Appropriations Subcommittee, which gets the lion’s share of discretionary spending. It’s also one of the 12 bills that, even in the current dysfunctional dynamic, has a better shot of passing on its own rather than as part of a continuing resolution.

“That is a hell of a lot of power and leverage,” Obey said.

Nevertheless, Obey, like most, was surprised by Leahy’s decision to pass on the chairmanship. “I had expected Pat to be the chair,” he said.