Arizona’s Jon Kyl, who was appointed to fill the late John McCain’s U.S. Senate seat after he died in August, announced he will step down from the post at the end of this year. Kyl was appointed by Arizona Gov. Doug Ducey in September. When appointed, Kyl committed to serving through at least this year, but said he would not run for re-election in 2020. “I have concluded that it would be best if I resign so that your new appointee can begin the new term with all other senators in January 2019 and can serve a full two (potentially four) years,” Kyl wrote in a now-released letter to Gov. Ducey. The governor will now pick a successor to serve until 2020, when there will be an election to fill the remaining two years of McCain’s term.