Dwight Pelz is fretting. "I'm worried about a lot of races," the chairman of the state Democratic Party says, sounding just as anxious as most top Democrats these days.

Here's why: Polls indicate that Republicans could easily take over the U.S. House of Representatives this fall—possibly the U.S. Senate, too—and here in Washington State, three close House races could not only help give Republicans more power in D.C., but could also flip the balance of power in this state's House delegation, which has been majority Democratic since 2001.