The U.S. Senate will soon have all 100 members in their seats.
Senator-elect Al Franken of Minnesota will be sworn in Tuesday.
A Capitol Hill worker installed the Democrat's nameplate outside his office Monday.
Franken brings the total number of Democrats in the Senate to 60.
On Monday, Majority Leader Harry Reid said he expects Franken to "deliver the change the country is demanding."
Franken lists health care and energy reform among his top priorities.
"I am going to work day and night to make sure that our kids have a great future and that America's best days lay ahead," he said. "I'm ready to get to work."
Franken, a former comedian, won Minnesota's Senate seat after an eight-month recount battle with Republican incumbent Norm Coleman.