TOPEKA ? Secretary of State Kris Kobach says he has no power under Kansas law to keep U.S. Sen. Pat Roberts off the ballot in the state’s Republican primary.

Roberts filed Friday for his fourth, six-year term in the Senate. He submitted the necessary paperwork shortly after tea party challenger Milton Wolf called on Kobach to reject any filing from Roberts.

Wolf argued that Roberts shouldn’t appear with him on the Aug. 5 primary ballot because Roberts doesn’t truly live in Kansas. Roberts said the argument is without merit.

Roberts owns a home in Alexandria, Virginia, but votes under a Dodge City address.

Kobach says under Kansas law, a filing is valid unless someone files a formal objection. Then a state board led by Kobach would decide the matter.