Democrats gain in Senate, Republicans gain in House; MIDWEST

Generally voters in the nation's heartland stuck comfortably with incumbents. But they also produced three of the nation's major US Senate upsets, and Democrats managed a net gain of one Senate seat in the region.

The most stunning upsets, both of GOP incumbents, occurred in Illinois and Iowa, where farmers have been particularly hard-pressed and the nation's economic recovery has been delayed. Bow-tied liberal Rep. Paul Simon (D) beat three-term Sen. Charles Percy (R). Mr. Simon spoke often of Illinois's loss of 26 percent of its manufacturing jobs over the last four years and of the state's high unemployment rate.

In Iowa, populist Rep. Tom Harkin (D) argued similarly that incumbent GOP Sen. Roger Jepsen, a conservative completing his first term, had not been as effective and as a strong a leader for Iowa as he could have been.

Republicans did pick up one unexpected new Senate seat in Kentucky. There, well-financed GOP challenger Mitch McConnell, a county judge from Louisville, struck a responsive chord with many voters in arguing that two-term incumbent Sen. Walter D. Huddleston (D) was too liberal for Kentucky's mainstream voters and had often missed important Washington votes.

But incumbents held their own in the five other Midwest Senate races. Democrats James Exon of Nebraska and Carl Levin of Michigan managed to keep a firm hold on their seats in spite of the Reagan landslide. And Republicans Rudy Boschwitz of Minnesota, Nancy Kassebaum of Kansas, and Larry Pressler of South Dakota all won reelection.