Astronaut Mark Kelly is sworn in as a senator from Arizona with his wife Gabby Giffords by his side

Mark Kelly was sworn in as the new Democratic senator from Arizona on Wednesday and will serve the remainder of late Republican Sen. John McCain’s term – reducing the Republican majority to 52-48.

The former astronaut who is married to former Arizona Rep. Gabby Giffords won the Senate special election last month and will have to run again in 2022 to retain his seat.

Giffords joined her husband for the swearing-in of Vice President Mike Pence on Capitol Hill Wednesday afternoon.

The former congresswoman resigned from office in 2012 after suffering severe brain damage following an assassination attempt in the form of a mass shooting at an event with 8th District voters of the Arizona Congress.

Former astronaut Mark Kelly (left) was sworn in as Arizona’s new Democratic senator by Vice President Mike Pence (right) on Capitol Hill on Tuesday. He was joined by his wife and former Arizona representative Gabby Giffords

Pence made small talk before the swearing-in ceremony, where he referenced Kelly's work as an astronaut and congratulated him on his Senate victory.

Pence made small talk before the swearing-in ceremony, where he referenced Kelly’s work as an astronaut and congratulated him on his Senate victory.

Kelly had been a captain in the US Navy and a NASA astronaut since the mid-1990s

Kelly had been a captain in the US Navy and a NASA astronaut since the mid-1990s

Here, Kelly (right) prepares for a third spacewalk while stationed on the International Space Station

Here, Kelly (right) prepares for a third spacewalk while stationed on the International Space Station

Back on Capitol Hill: Giffords was a Democratic congresswoman for Arizona's 8th congressional district from 2007 to 2012

Back on Capitol Hill: Giffords was a Democratic congresswoman for Arizona’s 8th congressional district from 2007 to 2012

Giffords and Democratic Senator Doug Jones greet each other

Giffords and Democratic Senator Debbie Stabenow exchanged words

She was greeted at the Capitol, safely touching elbows, by several Democratic lawmakers present for the swearing-in

Kelly and Giffords were joined by their daughters Claudia and Claire Kelly and Kelly's identical twin brother Scott Kelly (left speaking with Pence), who is also an astronaut

Kelly and Giffords were joined by their daughters Claudia and Claire Kelly and Kelly’s identical twin brother Scott Kelly (left speaking with Pence), who is also an astronaut

The couples arrive at the Capitol for the swearing-in ceremony

The couples arrive at the Capitol for the swearing-in ceremony

Stay safe: Kelly and Sen. Cory Booker touch elbows outside the Capitol in the new way to greet each other amid the coroanvirus pandemic

Stay safe: Kelly and Sen. Cory Booker touch elbows outside the Capitol in the new way to greet each other amid the coroanvirus pandemic

Giffords made his first major public remarks since his injury at the Democratic National Convention in August.

Kelly and Giffords stopped at John McCain’s grave to pay their respects before heading to Washington, DC for the swearing-in.

Shortly after Kelly was officially sworn into the Senate floors, he and his family gathered in the Old Senate Chamber and were joined by Pence for the swearing-in ceremony.

Pence spoke briefly about Kelly’s military service as a combat pilot before saying, “It’s an honor for me.” Congratulations.’

“You will be an invaluable voice building on the progress we’ve made,” Pence said in reference to Kelly’s astronaut background. “We put human space exploration back where it needed to be.”

Giffords, who served in the House with Pence for a few years, gave a brief “woo!” the sound and movement of the arms after the swearing-in ceremony.

Leaving Capitol Hill, Kelly answered his first press question as a senator saying it was important to pass the next coronavirus stimulus before January.

“Compromise is always a positive thing and we need a bipartisan approach to this. I don’t think it should wait until January,” he said.

Kelly defeated Republican Senator Martha McSally, who served in the interval between McCain’s death and the special election. Previously, McSally served as a congressman for Arizona’s 2nd congressional district.

The Arizona Senate seat is one of two Democrats who were able to swing in the Nov. 3 election.

Before heading to Washington DC, Kelly and Giffords stopped at the grave of the late Senator John McCain to pay their respects ahead of the swearing-in ceremony.

Before heading to Washington DC, Kelly and Giffords stopped at the grave of the late Senator John McCain to pay their respects ahead of the swearing-in ceremony.

Control of the Senate now rests entirely on the two second-round elections in Georgia next month, where Republican Senators Kelly Loeffler and David Perdue will face Democratic challengers.

If the Democrats win both elections, the Senate will be split 50-50, with the deciding vote coming from Democratic Vice President-elect Kamala Harris.

If the Republicans keep just one of those two seats, they will keep their slim majority.

Senator-elect John Hickenlooper, a Democrat, also flipped a Colorado Senate seat blue by defeating Republican Senator Cory Gardner in the November election.