Rove The political world is fixated on whether this year’s elections will deliver an epic rebuke of President Barack Obama and his party.

If that happens, it could end up costing Democrats congressional seats for a decade.

Some of the most important contests this Fall will be way down the ballot in communities like Ports- mouth, Ohio, and West Lafayette, Ind., and in neighborhoods like Brushy Creek in Round Rock, Texas, and Murrysville Township in Westmoreland County, Pa.

These are state legislative races that will determine who redraws congressional district lines after this year’s census, a process that could determine which party controls upwards of 20 seats and whether many other seats will be competitive.

Next year, legislatures in the 44 states with more than one congressional seat will adjust their districts’ boundaries to account for changes in population.

Some 18 state legislatures could have an additional task. As many as 10 states will have to combine districts as they lose House seats. Eight states are expected to gain at least one seat each.

Seats will almost certainly move out of Democratic states and into Republicanleaning, faster-growing states. Battleground states such as Iowa and Ohio might also lose seats. This process will be marked by a historic event: For the first time since joining the union in 1850, California will probably not get any additional seat in Congress.

Control of the state legislature matters whether a state loses or gains seats. Take fast-growing Texas, which is expected to pick up as many as four seats next year. Democrats had a 17-13 edge in the state’s congressional delegation after the 2000 elections.

Republicans won control of the Texas House in 2002 and redrew the state’s congressional map. As a result, the GOP now controls 20 congressional seats in Texas while Democrats control 12.

Similarly in Georgia, following the 2000 census Democrats redrew district lines to give themselves control of the state’s two new congressional seats.

In Pennsylvania, Republicans controlled 11 congressional seats and Democrats 10 before reapportionment cost the Keystone State two seats in 2001. Afterward, the Republican legislature redrew the map to the GOP’s advantage, creating 12 Republican seats and seven Democratic ones.

To understand the broader political implications, consider that the GOP gained somewhere between 25 and 30 seats because of the redistricting that followed the 1990 census.

Republican strategists are focused on 107 seats in 16 states. Winning these seats would give them control of drawing district lines for nearly 190 congressional seats.

Nationally, the GOP’s effort will be spearheaded by the Republican State Leadership Committee.

Karl Rove is former senior advisor to President George W. Bush.