According to the Pittsburgh Tribune-Review, Pennsylvania is likely to lose a Congressional seat. This has the implication of costing us an electoral vote (currently 21) in Presidential Elections.
Congressional representation is determined by the census. Constitutionally, we conduct a census every 10 years and reapportion representation according to population shifts. Basically, the tally is made and divided by the 435 seats in Congress. Pennsylvania also uses the census data to derive its State House and Senate districts.
In crafting a district’s lines, the State Senate must create a district that each has an equal number of residents and that the land be contiguous. Outside of that, the legislature can pretty much do as they please.
The 2000 census and subsequent district lines were cause for much debate and litigation. The new districts took several years to be implemented because of that.
When you look at the map of Congressional Districts, you will find that Pennsylvania’s 5th District is the largest by geography. This is a sparsely populated, mostly rural, mostly Republican district.
The Congressman representing the fifth district is also a freshman, first elected in 2008. No Congressman ever wants their district moved around much and will use their influence to try and keep things as usual. If any change is sought, it is usually to add members of their party to their district.
Beyond added opposition party members to their district, the biggest fear is likely an incumbent vs. incumbent matchup. This occurred with the last census between Republican Gerlach and Democrat Holden. Holden was successful.
Based on the fifth’s lack of seniority and geography that could be most easily split into other districts, my guess is that the fifth will be sacrificed to the 2010 census figures. The 3rd, 9th, 10th, 11th, 12th, and 17th districts could be lightly retooled to absorb the fifth. Every other district might have to be tweaked a little, but it would probably be relatively minor.
Because the party that controls the Senate in Pennsylvania will ultimately derive the plan, the redistricting normally favors that party. While the fifth is a Republican district, they could conceivably add Republicans to the aforementioned districts by combining through absorption of the fifth.
The only really significant pocket of Democrats in the fifth is found in State College. Republican Shuster (9th) would probably prefer Democrats be added to Democrat Murtha (12th) than his own district.
The variations of any redistricting plan are enormous. With Republican control of the Senate, I would wager that the plan will include increasing Republicans into districts that were casualties of the 2006 and 2008 Elections. This effort can be an end-run to try and recapture the Pennsylvania Congressional Delegation.