PHOENIX — Arizona Sen. Martha McSally will officially be seeking re-election come November 2020.

The news comes as no surprise, but McSally's team confirmed to 12 News Tuesday that the senator filed for the election back in January.

READ: McSally visits Luke Air Force Base while pushing for reforms to address sexual assault in the military

McSally, who lost her 2018 bid for Jeff Flake's former Senate seat to Sen. Kyrsten Sinema, was appointed by Gov. Doug Ducey just over a month later to fill the seat of the late Sen. John McCain.

Ducey appointed McSally after Sen. Jon Kyl, his previous appointee, resigned at the end of the year.

WATCH: Gov. Ducey and Congresswoman McSally discuss her U.S. Senate appointment 

McSally's 2020 Democratic opponent could be Mark Kelly after Rep. Ruben Gallego said Monday he won't run for the U.S. Senate.

READ: Rep. Ruben Gallego declines to run for Arizona Senate seat

The retired NASA astronaut announced he was running back in February.

The winner of the 2020 race will then have to run again in 2022 when John McCain's unfinished six-year term officially ends.

MORE: Arizona will have 3 more US Senate elections by the end of 2024

Recently, McSally was among Arizona's congressional leaders who responded to the release of special counsel Robert Mueller's report regarding investigation of Russian electoral tampering.

READ: Arizona congressional leaders respond to Mueller report

She tweeted that it "wasted time and energy."