Mark Greenbaum asks, pointing out that 2011 will be the first year since 1961 when a Democratic White House has a say in redistricting. If it wants to have a say.
Collectively, Republicans could net 15 new seats nationwide by imposing a series of brutal maps. But gerrymanders of this scale would likely violate the spirit, if not the letter, of the Voting Rights Act. Any violation would have to be pursued by the Obama Justice Department, on the grounds that the new districts unlawfully minimize minority voting rights.
To understand what could go wrong for Democrats here, look at Texas and Florida. Florida was gerrymandered in 2001, and Texas was re-gerrymandered in 2003, both by Republican-only teams. Florida, you will remember, split 50/50 between George W. Bush and Al Gore in 2000. But Republicans managed to draw a map giving Republicans 18 seats to seven seats for Democrats. This was done by creating snaking, super-safe seats for black Democrats Corrine Brown, Carrie Meek, and Alcee Hastings, while creating Republican-leaning suburban counties in the rest of the state. In 2008, the Democrats manage to claw three of those suburban seats over their side to have 10 of the state's 25 seats, even though Barack Obama was carrying the state over John McCain. The 2003 redistrict of Texas went much the same way, with swing districts that elected Democrats like Charlie Stenholm and Martin Frost obliterated to create super-safe minority districts and just-as-safe Republican-leaning suburban seats.
The way the Voting Rights Act is usually interpreted, this is fine. If Obama's DOJ wanted to fight state plans like this, it could, but it would be, obviously, ugly, and called out as a "power grab." The most they can do, possibly, is hold out the threat of challenging plans that screw over Democrats in the name of giving Al Green or Alcee Hastings or whoever a safe seat.