John McCain’s replacement Senator John Kyl has announced his retirement at the end of the year.

According to Fox News:

Sen. Jon Kyl is resigning from the seat he was appointed to less than four months ago following the death of John McCain, Arizona Gov. Doug Ducey announced Friday. Kyl’s decision means the Republican governor will need to appoint another replacement lawmaker.

The decision by Kyl, 76, was not unexpected. He had retired from the Senate in 2012 and said when he took the appointment in September that he only committed to serving until the end of the year. His resignation is effective Dec. 31.

Ducey sidestepped selecting a longer-term replacement after McCain died on Aug. 25, saying he picked Kyl because he was “the best possible person, regardless of politics” for the job. But Kyl made it clear he only agreed to the appointment out of a sense of duty and had no plans to stay in the job for long.

The choice of the well-respected former senator to fill McCain’s seat allowed the Republican governor to avoid controversy in the midst of his re-election bid, but also nearly assured that another vacancy would come soon. Now all attention is on Ducey’s pick, who will serve until a special election in 2020 allows voters to select the person who fills the final two years of McCain’s six-year term.

Many are speculating that Martha McSally will replace kill who was in his second stint in the Senate. She ran unsuccessfully for the Senate in November.