If the Democrats think tonight looks bad, wait till they see the next decade. Republican gains in the 2010 midterms won’t stop with the U.S. Congress–the GOP wave could help them take from 10 to 18 state legislatures from the Democrats. Winning at the state level in 2010 will put them in position to control the once-per-decade congressional redistricting that determines the shape–and often the partisan tenor–of congressional districts. A similar advantage in 1991 paved the way for the GOP’s historic 1994 wave. Presently, the Democrats control both legislative chambers in 27 states, the Republicans in 14, with power split between the parties in eight states. Republican control of redistricting could put them in position to extend their majority over the next decade.