MASSACHUSETTS REPRESENTATIVES AND SENATORS have for decades enjoyed key committee and leadership posts in Congress because of their seniority, and the state has reaped the benefits, both in funding from Washington and in policy advantageous to the state.

Before his death in 2009, Sen. Edward M. Kennedy delivered funding for state projects ranging from the Big Dig to the federal courthouse in Boston. He was “irreplaceable,” says Ronald Weich, a former Kennedy aide who is now dean of the University of Baltimore School of Law. Add in the loss through retirement of US Reps. William Dela­hunt, Barney Frank, and John Olver, and the resignation in February of Sen. John Kerry, and the state’s congressional delegation starts to look a lot like this year’s Red Sox—a team with a lot of new faces.

When Kennedy died, the Massachusetts congressional delegation was approaching 200 years of combined service in Congress. Now the delegation has less than 125, and that number could drop even further if one of the Democratic congressmen running for Kerry’s seat prevails and becomes a rookie senator. Will the state’s clout in the corridors of Congress fall with it?

David Hopkins, a political science professor at Boston College, says the blow to the state’s seniority is no reason to despair. The loss in seniority matters in Washington, he says. “But not a lot.”

Senior members of Congress have historically controlled the flow of legislation through their committees and have had more opportunity to add funds for home state projects. But a series of changes over the last six years, most notably the concentration of power among party leaders instead of committee chairmen, the banning of funding earmarks, and two tidal wave elections, in 2006 and 2010, are making seniority less of a factor.

Today, key legislation in Washington is often written by just a few party leaders without the input of committee chairmen. The situation is similar to what’s happening in Boston on Beacon Hill, where power is concentrated in the hands of the governor, the House speaker, and the Senate president. In Congress, President Obama, Senate Majority Leader Harry Reid of Nevada, House Speaker John Boehner of Ohio, and the top Repub­lican in the Senate, Mitch McConnell of Kentucky, are the key players.

Party leaders in Washington are pledging this year to return to “regular order,” in which bills advance from subcommittees to committees to the floors of the House and Senate, and then to House-Senate conferences where the two chambers reconcile their respective versions. But that isn’t the way the process has worked in years. Con­sider the New Year’s fight over the fiscal cliff, in which Obama, McConnell, and Reid brokered a deal in private. Or the 2011 legislation negotiated by Obama and Boehner that averted a government default. The last time Congress was able to pass all of its spending measures under regular order was 1994.
Earmarking, the legislative practice of steering funds to lawmakers’ pet projects back home, is also gone. Under pressure from deficit hawks, the House banned the practice in 2010 and the Senate followed in 2011. Both moves lessened the power of the House and Senate appropriations committees.

The appropriations committees have declined as power centers to such a degree that earlier this year Democratic Sen. Patrick Leahy of Vermont turned down the Senate Appropriations Com­mit­tee’s chairmanship to stay on as the chairman of the Judi­ciary Committee. At Appropriations, he would have overseen a shrinking federal budget with no earmarks. At Judiciary, Leahy has a hand in this year’s two big policy debates: immigration and gun control.

The second most senior Democrat didn’t want the job either. Iowa’s Tom Harkin turned down the position to remain the chairman of the Health, Education, Labor, and Pensions Committee. (In January, Harkin also announced that he won’t seek reelection next year.)

“The reduced importance of appropriations changes everything,” says Izzy Klein, a former aide to US Rep. Edward Markey of Malden as well as New York Democratic Sen. Charles Schumer. Now, Klein says, representatives and senators acquire power by “transcending committee seniority and making their issues national in scope.”

Massachusetts still has representatives capable of flexing power in this new environment. In the House, Somer­ville’s Michael Capuano, a senior Democrat on the Trans­porta­tion and Infrastructure Committee, is close with Demo­cratic leader Nancy Pelosi. Worcester’s Jim McGovern is the second-ranking Democrat on the Rules Committee, which controls the procedures for considering bills on the House floor. Should the Democrats retake the House, Springfield’s Richard Neal could ascend to the chairmanship of the tax-writing Ways and Means Committee.

The House delegation might take a blow if its dean, Markey—with 36 years of seniority and the top Demo­cratic seat on the Natural Resources Com­mit­tee—moves to the Senate. He’s competing for the Democratic nomination with Stephen Lynch, who has spent 11 years in the House and sits on the Financial Services Committee.

 “With all these people moving on, we are going to take a hit. With seniority comes clout,” says McGovern. “But we’ve been through this before. What I’ve learned over the years is that we have a very adaptable delegation.”

McGovern and Capuano are among the most senior remaining House members—Neal will be the new dean if Markey wins his Senate race—but their ties to Demo­cratic Party leaders make them more important than their seniority alone would indicate. Between them, there’s “a huge amount of clout,” says David C. King, senior lecturer in public policy at Harvard’s John F. Kennedy School of Government. “They don’t have the same policymaking expertise of Barney Frank, but Capuano deals in raw power. He has influence over every policy domain through his relationship with leadership. And then McGovern as part of the Rules Committee is at the pinch point in the funnel that controls access to the floor.”

The rest of the delegation is well represented on the House’s authorizing committees, such as the Education and the Workforce Committee and the Armed Services Com­mittee, which now have more power over federal funding than appropriators because the authorizing committees determine the maximum amount that appropriators can spend. Authorizing committees also draft the language that influences how grantmakers at Obama administration agencies direct funds back to state projects.

Massachusetts has seats on 15 of the 21 House committees, including those with authority over the budgets of most federal agencies. The state no longer has a seat on the Appropriations Committee since Amherst’s Olver retired at the end of 2012 and his district was eliminated as part of the redistricting process.

In the Senate, Massachusetts’ situation would appear grave, if seniority were the only determinant of power. Democrat Elizabeth Warren, who defeated Republican Scott Brown in November and now holds Kennedy’s old seat, ranks 97th in seniority. Kerry’s interim replacement, Democrat William “Mo” Cowan, is dead last. (Senate seniority is based on service in the upper chamber, with ties broken by factoring in previous years as a House representative, presidential cabinet member, or governor. If there are still ties after that, states with greater populations go first.)

Warren may prove more influential than her seniority would indicate. A former Harvard Law School professor, she arrives in Washington with a reputation for policy expertise and a knack for attracting media attention, as she did during recent banking hearings.

“Liberal activists know who she is,” says Hopkins. She has the ability to command a national audience, he says.

States with deeper benches—Massachusetts now has nine representatives to go with its two senators—tend to recover more quickly from a hit to their seniority, especially if the new blood arriving in Washington is ambitious. Tennessee, which also has an 11-member delegation, lost two influential Republican senators between 2002 and 2006, first Fred Thompson, the chairman of the Governmental Affairs Committee, and then Bill Frist, who resigned as Senate Majority Leader. But the state now has a top appropriator in Sen. Lamar Alexander and an influential voice on foreign policy in Sen. Bob Corker.

Hopkins points out that Massachusetts’s loss in seniority comes at a time when Congress as a whole is less experienced than it has been in many years. Over the last six years, more than half of the House and Senate has turned over, an unusually high rate of upheaval prompted by the Democratic wave of 2006 and the Republican one in 2010. The retirement announcements this year of Senate Demo­crats Jay Rockefeller of West Virginia and Harkin mean that no more than four Democrats in the upper chamber will have more than 28 years of seniority when the next Congress convenes in January 2015.

Since Massachusetts has a long history of re-electing incumbent Democrats—none has lost since US Reps. Nick Mavroules and Joseph Early in 1992—it might not take long for Massachusetts lawmakers to move up.