The electoral ouster of Rep. Barbara Comstock (R-Va.) Tuesday means that Democrats will make up the entire congressional delegation representing the immediate Washington area, marking the first time in at least 50 years that one party has had such dominance.

The political monopoly means the local delegation — comprising four U.S. senators, eight members of the House and one delegate whose districts are inside the Capital Beltway or reach close to it — will enjoy unprecedented unity as it deals with issues such as extending federal funding for Metro and protecting federal workers.

But it also is raising concerns that the region will lose some valuable bipartisan flavor, especially as it deals with a Republican in the White House who has little sympathy for the capital area that he routinely mocks as a “swamp” that needs to be drained.

In recent years, Comstock has been the lone Republican in Congress representing constituents in the close-in Washington suburbs. Like her longtime predecessor in the seat, Frank Wolf (R), Comstock sought to capi­tal­ize on her unique status by telling voters they needed a Republican voice speaking up on regional issues. Comstock’s district includes Loudoun and parts of Fairfax and Prince William counties.

But in an election that became a referendum on President Trump, Comstock lost to state Sen. Jennifer Wexton (D-Loudoun), whose campaign stressed that Comstock voted 98 percent of the time with the president.

“There is a risk of just one party representing the whole D.C. metro area,” said Dan Scandling, a longtime former top aide to Wolf. “In the past, when you had a Republican in the White House, a local Republican in the room could temper . . . some of the venom directed at the federal workforce.”

Scandling said a GOP member of Congress also aided in obtaining funding for Metro, local airports and other forms of transportation.

“Having that other side of the aisle, [so] it doesn’t just look like it’s pulling in pork, can be very helpful,” he said.

Echoing Scandling’s concern — perhaps surprisingly — was liberal Rep. Don Beyer (D-Va.), whose district includes Arlington, Alexandria and parts of Fairfax County.

It’s “a reasonable argument” to favor a bipartisan delegation, Beyer said. “I think balance is really good.”

Beyer has introduced legislation that would address the problem by reviving multi-member congressional districts, which were widespread in the United States until the early 1840s. Such a system would lead to more proportional representation, he said, conceding it was “a long-term project” that had little support at present.

Other analysts said that in today’s politically polarized environment, it was harder for Comstock to cooperate with Democrats than it had been for Wolf and another longtime Northern Virginia Republican congressman, Tom Davis III. Bipartisan cooperation in the region played a key role in getting federal funding to rebuild the Woodrow Wilson Bridge, for instance, and Davis helped lead the successful campaign for federal funding for Metro 10 years ago.

“You need the delegation working together for the interests of the region,” said Mark J. Rozell, dean of the Schar School of Policy and Government at George Mason University. “In the current climate, it’s just easier to get people from the same party to be in sync with each other.”

Rozell said there was some downside to Comstock’s departure, however. “What the region loses, of course, is a member who has some seniority and great familiarity with the players,” he said.

In other federal races in districts with constituents in the immediate Washington region, two Democrats were easily reelected to the U.S. Senate: Benjamin L. Cardin (Md.) and Tim Kaine (Va.). They join incumbent Democratic senators Chris Van Hollen (Md.) and Mark R. Warner (Va.).

In races for the U.S. House, six Democratic incumbents from the area won reelection: Beyer and Rep. Gerald E. Connolly in Virginia, and Reps. Anthony G. Brown, Steny H. Hoyer, Jamie B. Raskin and John Sarbanes in Maryland.

In addition, businessman David Trone (D) won an open seat to succeed Rep. John Delaney (D) in Maryland, and Del. Eleanor Holmes Norton (D) easily was reelected in the District.

The only Republican representing a district near Washington is now Virginia Rep. Rob Wittman, who was reelected and whose district stretches into southern Prince William County.

The last time one party had anything approaching the monopoly that Democrats will enjoy in the immediate area was in the early 1970s, when Republicans dominated the region. Even then, independent Harry F. Byrd Jr., who previously had been a Democrat, held a U.S. Senate seat in Virginia. And the District had a Democrat as its nonvoting delegate, Walter E. Fauntroy.

One bright spot for local Republicans Tuesday was the reelection of Maryland Gov. Larry Hogan. His victory, together with the reelection of District Mayor Muriel E. Bowser (D), raised hopes that the region’s top three executives can cooperate even if the congressional delegation is at odds with the White House.

Hogan, Bowser and Virginia Gov. Ralph Northam (D) cooperated effectively in winning dedicated funding for Metro for the first time in its 42-year history.

“I would really encourage the two governors and mayor to think about how to work together,” Jack McDougle, chief executive of the Greater Washington Board of Trade, said. “They’re pragmatic. If ever we’ve had an opportunity to come together and think about some regional strategies, then this is it.”