U.S. Rep. Roscoe Bartlett is fighting to hang on to his seat after 20 years representing Western Maryland.

Two years ago the Sixth Congressional District was 47 percent Republican and 36 percent Democrat, data from the state Board of Elections show. After the state redrew the state's congressional map in a once-a-decade redistricting process, the district lost Carroll, Howard and much of Frederick counties and gained part of liberal Montgomery County, becoming 44 percent Democrat and 33 percent Republican.

The district is the ninth least compact congressional district in the country, according to a report released Tuesday by Philadelphia geospatial analysis firm Azavea. It has been heavily criticized as blatant gerrymandering by numerous state and local elected officials, including Maryland Comptroller Peter Franchot and other Democrats, and a measure on the ballot could overturn the congressional districts the legislature passed last year.

Voters registered in the Sixth District
  2010 2012
Democrat 159,715 192,820
Republican 208,024 145,620
Green 1,159 1,045
Conservative 122 Not Listed
Libertarian 1,353 1,458
Unaffiliated 73,262 94,074
Other 2,044 2,077
Total 445,679 437,094

But as a result, Democrats now have a shot at winning the district for the first time -- Real Clear Politics rated it one of the most likely districts to switch parties from Republican to Democrat -- and Potomac financier John Delaney is trying to unseat the Republican incumbent.

If money is any indicator, Delaney may be succeeding.

Between Oct. 1, 2011, and Sept. 30, 2012, Delaney raised $1.8 million -- $1.4 million of which came from individuals -- and loaned himself another $1.7 million, Federal Elections Commission filings show. By comparison, Bartlett raised $1.1 million between Jan. 1, 2011, and Sept. 30, including $600,926 from individuals.

"Delaney has been working harder for the seat, and there's been sort of little evidence of Bartlett working to win over his new voters in Montgomery County, [which is now] the seat of power," said Todd Eberly, a political science and public policy professor at St. Mary's College of Maryland.

Eberly attributed this partly to previous elections when Bartlett barely had to campaign to keep his seat.

Bartlett Campaign Manager Ted Dacey disputed the notion that Bartlett isn't campaigning. "He's working very aggressively in this cycle and to hold on to the seat for Republicans."

Both campaigns declined to release internal polling data.

But the election is far from decided. Several of the seven ballot questions facing Maryland voters -- like the Maryland Dream Act, same-sex marriage and a gambling expansion -- as well as a contentious presidential election may drive more conservative voters to the polls than usual in the overwhelmingly Democratic state, Eberly said. That voter turnout "could be enough to carry Bartlett over the finish line."