Mike Braun was sworn in as Indiana’s newest U.S. senator Thursday.

The businessman and former state lawmaker defeated Democrat Joe Donnelly in the November election.

Braun said winning the election and assuming office means a lot to him.

“When I look at it in the context that I spent 15 months out campaigning, through early August and the conclusion in November, it was quite a journey,” Braun said. “And I’ve done a lot of interesting tasks in my life, and building a business, mostly. But when it comes to the pound of a campaign for six days a week, 14 to 18 hours a day, you can’t really realize until you do it.”

Other new lawmakers were also sworn in, as it is the first day of the new Congress.