Milton Wolf, the tea party candidate challenging Sen. Pat Roberts (R-KS), is asking the Kansas secretary of State to kick Roberts off the ballot for re-election because Roberts doesn’t have a home in Kansas.

Wolf’s campaign argues that Kansas Secretary of State Kris Kobach (R) is required to reject Roberts’ application under the U.S. Constitution, which requires that a senator “be an inhabitant of that State for which he shall be chosen.”

“When Senator Roberts files his paperwork later today, he will likely use the address [for] a single-family home in Dodge City where he claims to rent a bedroom. However, Senator Roberts doesn’t stay at that address,” the letter from Wolf’s campaign read. “When the owner was asked earlier this year how many times Senator Roberts has stayed at that address since he allegedly began renting the room in October 2013, he couldn’t remember.”

Wolf’s campaign has been relentless in trying to paint Roberts as a fake Kansas resident after The New York Times reported that Roberts does not own a home in the state and instead, when he needs to use a Kansas address, uses one for a residence owned by two donors to his political campaign.

Read Wolf’s full letter here.