Rep. Steve King (R-Iowa) won reelection Tuesday, turning back a challenge from former Iowa first lady Christie Vilsack (D).

(Alex Brandon/Associated Press  )

With 84 percent of precincts reporting, King led Vilsack 55 percent to 43 percent. The AP has called the race for him.

King, a favorite of the tea party, will begin his sixth term in the House next year.

Vilsack, the wife of former Democratic governor and current U.S. Agriculture Secretary Tom Vilsack, ran a strong and well-funded campaign. But it wasn't enough to overcome the GOP tide of Iowa's 4th district in the western and central part of the state.