The Dems didn't so much go out of their way to get Morrella as they stopped short of trying to get Bartlett. The MD-08 district had to lose precincts in the 2000 round of redistricting and whether they took the southwest half of MontCo or the southeast half they would've ended up with a more heavily Dem district than the MD-08 district of the Nineties. Now, if it weren't for Morrella the Dems could've tried being more adventurous and went after Bartlett, but as it were MD-08 is a fairly regular district in terms of geography.
The real contortions were with MD-02 and MD-03, and that, of course, was to ensure that the Ehrlich seat would also go Dem:
I personally rather doubt the Dems could wring another seat out of Maryland. I don't see how you get either MD-06 or MD-01 to majority Dem without making one of the six Dem seats a very difficult hold.