This is the 15th in an occasional series that focuses on the decennial redistricting process in key states. We call it “Mapping the Future”. The series aims to look forward to how the maps in these states could be drawn and what the best and worst outcomes for each party might be. Today we take on Maryland. (And make sure to check out the first 14 installments: Texas, Indiana, Georgia, Illinois, Massachusetts, Ohio, California, Nevada, Virginia, Pennsylvania, Florida, Utah, North Carolina and Wisconsin.)

Democratic state legislators in Maryland enacted one of the most effective gerrymanders in the country in 2001, successfully turning a four-to-four split in the state’s congressional delegation into a six-to-two Democratic advantage by 2002.

With Democrats again in charge of the redistricting process in 2011 and with the delegation still at a six-to-two edge for the party, the question now is whether they can rid the state of one of those remaining GOP districts.

It will take some doing, but with Democrats having very few chances (outside of Illinois) to create new winnable seats for their party, Maryland presents a rare opportunity.

The most likely target in the redistricting process is freshman Republican Rep. Andy Harris, who helped Republicans reclaim a conservative Eastern Shore district from one-term Rep. Frank Kratovil (D) in November.

The 1st district was drawn in 2001 as one of the two solidly Republican districts, but thanks to Harris’ defeat of centrist Rep. Wayne Gilchrest in the 2008 GOP primary, Kratovil was able to eke out a win that November.

Now Democrats are hoping Kratovil will run again, but in order to entice him they may need to draw him a friendlier district. The good news for Democratic recruiters is that strengthening the seat slightly for their side is possible. The bad news is it’s going to be tough to make the seat significantly better.

Here’s how Democrats might be able to get Harris and win back the 1st. (Be sure to follow along on the congressional map here):

Democratic line-drawers would move the state’s other Republican district -- Rep. Roscoe Bartlett’s northern 6th district -- east to take in the most conservative parts of Harris’ 1st district, which runs from the Baltimore suburbs across the Chesapeake Bay and to the Eastern Shore.

Harris ran up his biggest margins in 2010 in suburban Baltimore County and Harford County, which happen to be the easiest areas to move into Bartlett’s district. From there, Harris’s 1st district could move into more Democratic areas outside the Eastern Shore, such as Aberdeen, Annapolis and Prince George’s County in the Washington, D.C. suburbs.

But in order to move that territory around and make a real change in Harris’s district, the state’s Democratic members of Congress are going to have to play ball. And it’s still very much an open question whether they will do that.

In order to move Bartlett’s district east, Rep. Chris Van Hollen’s (D) suburban Washington 8th district would have to shift north to take some of Bartlett’s territory in Frederick County.

Some of fast-growing Prince George’s will likely have to move out of House Minority Whip Steny Hoyer’s (D) 5th district, but Rep. Elijah Cummings (D) would very much like that territory added to his 7th district rather than the 1st.

And, adding Aberdeen and Annapolis to the 1st would come at the expenses of Rep. Dutch Ruppersberger’s (D) 2nd district and Rep. John Sarbanes (D)’ 3rd district, respectively.

Both Ruppersberger and Sarbanes, despite having generally safe districts, have reason to be wary. Each of them saw their districts underperform for Gov. Martin O’Malley (D) in the 2010 governor’s race. And Sarbanes’ 2006 primary win came because of his overwhelming strength in Annapolis-based Anne Arundel County. Losing that area could give him heartburn if a primary challenge were ever to develop.

Put plainly, targeting Harris requires a lot of moving pieces.

“For this to happen, Elijah can’t get better, Sarbanes can’t get better and Ruppersberger can’t get better,” said a Maryland Democrat tuned in to the redistricting deliberations. “There’s a lot of pain to go around.”

The question for Maryland Democrats is whether it’s worth it.

Even if these Democratic members of Congress allow the state legislators everything they want in the new map, Harris’ district will still be very much a swing one. It went 40 percent for President Obama in 2008, and any changes are unlikely to make it anything more than a toss up seat.

While Kratovil has a record as a strong campaigner and would benefit from adding territory in Prince George’s (where his father of the same name was a well-known judge), it’s hardly a guaranteed win for Democrats in the years ahead. And if you can’t convince Van Hollen, Cummings, Sarbanes and Ruppersberger that the changes will lead to an extra seat, they may not want to make the changes at all.

(Keep in mind – individual members’ preferences matter A LOT in redistricting.)

The more likely outcome, say informed Democrats, is a few concessions here and there from these members that turn Harris’ district into a district that would have gone 45 percent-plus for Obama – giving their party a chance to win the seat going forward without badly overextending everyone else.

And as long as they can extend Bartlett’s district into Baltimore County, they will create a real headache for Harris. That’s because that’s the congressman’s home area would suddenly be absorbed into Bartlett’s district. (Harris did buy property on the Eastern Shore in 2008, though, so he does have a footprint there.)

With Bartlett in his mid-80s, does Harris run for reelection to his current seat or turn his attention to running for the state’s lone safe Republican district when the longtime congressman retires?

Either way, things will get more difficult for Harris. Democrats just need to decide whether they want to go to a lot of trouble for an extra seat that might — but also might not — be winnable or holdable in the long term.

With so few opportunities to add seats this year national Democrats may be willing to take the gamble. But can they convinced Maryland’s Democratic delegation to go along?