A northeast Kansas prosecutor has opened his campaign for the U.S. Senate seat by criticizing three-term Republican incumbent Pat Roberts for moving to the right on issues.

Shawnee County District Attorney Chad Taylor’s kickoff news conference Friday made him the first Democratic candidate in the race. Roberts is seeking re-election but faces a GOP primary challenge from Leawood radiologist Milton Wolf.

Taylor said that Roberts has lost touch with Kansas values and has moved to the far right.

But Roberts spokesman Leroy Towns said Taylor will have to defend President Barack Obama and fellow Democrats in Washington.

Taylor was first elected district attorney in the county that includes Topeka in 2008 and was re-elected in 2012.

A Democrat hasn’t won a Senate race in GOP-leaning Kansas since 1932.