In the past several months, the Washington, D.C., policy world has begun a necessary and constructive debate over how to “depolarize” the nation’s politics. Scholars Thomas Mann and Norman Ornstein, for example, have made a compelling case for a suite of structural improvements to the political system, including redistricting and campaign finance reform.

But while most proposals have looked to fix the political system in the big picture, another place to look to reform might be Congress’ internal workings as well. In particular, Congress should consider scrapping seniority as the basis for deciding committee chairmanships, especially in the House, where individual Members have much less power than in the Senate.

Aside from leadership, committee chairmen are among the most powerful Members of Congress. They decide the legislative agenda, broker deals on major bills and shepherd them through Congress. They wield enormous influence over their colleagues and command prodigious fundraising ability.

Currently, they are largely chosen on the basis of longevity (and the approval of party leaders). But a better system might be to choose committee chairmen by the same secret ballot process by which rank-and-file Members choose such top leadership posts as Speaker and caucus chairman.

This would open up chairmanships to any Members — even the most junior — who can roust up even votes to convince their peers of their credentials for chairing a committee.

In combination with other systemic changes, this reform could shake the entrenchment of polarized interests and reward Members with the best ideas. Most importantly, it could level the field for moderates, who rarely survive long enough to become chairmen.

Because chairmanships are a reward for longevity, they’re also likely to be held by Members in “safe” seats, while moderates from swing districts (by definition volatile) are effectively shut out. Even among Republicans, who term-limit their chairmen, committee chairmen still tend to be among the most senior Members of the caucus — the vast majority of whom hail from safe seats.

The 24 members of the Blue Dog Coalition, for example, have been in the House for an average of five terms. In contrast, the chairmen and ranking members of the House’s most powerful committees — Ways and Means, Energy and Commerce, Appropriations, Rules, Education and the Workforce, and Financial Services — have been in Congress an average of 14 terms. In fact, two-thirds of these top committee members were elected in the 1970s and 1980s (while the most senior Blue Dog — Minnesota Rep. Collin Peterson — was elected in 1990).

The inability of moderates to rise in a seniority-driven committee structure entrenches Washington’s polarization in several ways.

First, it deprives committee leadership of the very Members equipped to carry out the pragmatic, bipartisan lawmaking that Washington desperately needs.

Moderate factions such as the Blue Dogs and the New Democrat Coalition have been at the front lines of every major bipartisan piece of legislation passed by Congress in the past several years, including education reform, trade agreements and recent efforts to boost startups and small businesses.

In many cases, their role has been to nudge party and committee leaders toward the center, where proposals have better odds of passing.

Second, the relative lack of moderates among top committee members means many Americans’ viewpoints are underrepresented. According to Gallup, more than a third of Americans consider themselves to be “moderate,” while just 10 percent see themselves as “very conservative” and only 6 percent say they’re “very liberal.”

Yet, of the 12 top Members of the marquee House committees named above, none are Blue Dogs or New Democrats while just three are members of the semi-moderate Republican Main Street Partnership.

Finally, by essentially reserving the benefits of chairmanships to safe seats, the seniority system makes already-vulnerable moderates even less secure.

Being a committee chairman is powerful protection for incumbency, given its attendant influence and fundraising ability. But Members in safe seats need that boost the least. Among House Democrats in 2010, for example, New Democrats and Blue Dogs spent twice as much as their colleagues in the Congressional Progressive Caucus to keep their seats. They were also much more likely to be the targets of outside spending.

The Cook Political Report predicts there will be just 96 swing districts after this year — a 40 percent drop since 2000. This means an ever-diminishing center and a growing no-man’s land between increasingly divided poles. More so than ever, moderates will be a vital bridge between the two poles — if they’re around.

As former Rep. Brian Baird (D-Wash.) told the Wall Street Journal, “There is a wisdom that comes with greater years. … But sometimes in Congress that isn’t the case with everyone. We’d be better off with picking chairmen on the basis of who has the best ideas and vision rather than longevity.”

While efforts to weaken the seniority system have been attempted before, the need for reform is more urgent than ever. Ending the seniority system would not only reward merit over longevity, it would give more voice to the much-needed and increasingly vital center.

Anne Kim is managing director for policy and strategy at the Progressive Policy Institute.