TOPEKA, Kan. (AP) — A northeast Kansas prosecutor has won the Democratic nomination for the U.S. Senate, but faces a difficult fall campaign in the Republican-leaning state.

Shawnee County District Attorney Chad Taylor prevailed over Lawrence attorney Patrick Wiesner in Tuesday’s primary. Taylor had the backing of party leaders.

Taylor was elected district attorney in the county that includes the state capital of Topeka in 2008 and re-elected without opposition in 2012.

Wiesner ran unsuccessfully for the Democratic nomination for the Senate in 2010.

Taylor will be seeking the seat held by three-term Republican incumbent Pat Roberts.

Republicans enjoy a nearly 20 percentage-point advantage among registered voters and have won every U.S. Senate race in Kansas since 1932.