To get a good feel for Maryland's Eighth District, one needs only to travel north from Washington D.C. up Wisconsin Avenue, through the upscale shops of Chevy Chase and into Bethesda, one of the nation's wealthiest suburbs and home to some of the best-educated, most politically savvy voters in the country.

As David Brooks, a NewsHour regular and author of Bobos in Paradise: The New Upper Class and How They Got There, describes them, Bethesdans are "urban exiles" who prefer "anti-chain chain stores that cater to people who consider themselves too refined and individualistic to shop at the mall or the mass-market big-box stores."

Beyond Bethesda lies the National Institutes of Health, one of the many federal government organizations hidden behind the trees lining Montgomery County's roadways. The Food and Drug Administration and the National Institute of Standards and Technology are also based in Maryland Eight, as are many of the people who work there.

Still further, up Interstate 270, which juts from the Capital Beltway, stands part of Maryland"s thriving tech corridor that Time Magazine called "DNA Alley". Montgomery County, which makes up the bulk of Maryland Eight, is the home of firms like Celera and Human Genome Science, pioneers in the study of the human gene.

The Maryland Eight electorate is uniquely independent-minded. It has chosen a moderate Republican representative for 32 of the past 40 years. However, no district in the country represented by a Republican gave Al Gore a higher percentage in the 2000 presidential election.

The detail-oriented and informed nature of this district's voters is illustrated in a story told to The Washington Post by Michael Barnes, who served Maryland Eight in Congress until 1986. Riding to work on the Metro subway system one morning, Barnes was approached by a constituent.

"Congressman, I just want to thank you for your vote last night on the previous question to the rule," the constituent said.

Barnes has often told that story to colleagues to show how Congress-savvy Maryland Eight voters can be.

The current representative, Constance Morella, has compiled one of the most liberal voting records of any House Republican. She has been able to hold together a majority by reaching out to a population that has become increasingly diverse with each passing year. What was once a primarily white suburb is now an immigrant magnet with one in four residents a minority.

However, the Maryland's recent redistricting efforts have drastically changed the political make-up of Morella's constituency. The new district no longer contains the more conservative voters of northern Montgomery County. Instead, the Democratic-led Assembly added the much more liberal areas near Silver Spring and Takoma Park and several heavily African American precincts in neighboring Prince George's County.

Morella has called the redistricting process "tyrannous" and "an insult to the people."

The Cook Political Report calls Morella the most vulnerable Republican incumbent in the House, and says the tough eight-term veteran is in the fight of her political career.

Democrats say Morella tops their list of Republicans they need to defeat in order to wrest control of the House away from the GOP. And the pressure is mounting on liberal special interest groups -- environmentalists, gun control and abortion rights advocates -- to end their support of the independent Republican and put their weight behind her Democratic challenger.

It remains to be seen whether Morella can hold on to the critical groups she'll need in November, including Democratic women and the growing numbers of Hispanic and Asian American voters.

--By Leah Clapman, Online NewsHour