Sen. Amy Klobuchar has joined a growing chorus in Congress calling for Republicans and Democrats to sit together at the State of the Union.

Klobuchar has joined a letter drafted by Sen. Mark Udall of Colorado that's receiving bipartisan support for mixing the two parties at the president's annual address later this month.

If Udall's plan were to take shape, it would end a longstanding custom in Congress. Traditionally, Democrats and Republicans sit on opposite sides of the House floor as the president delivers his speech, the president's party cheering often while the opposition remains silent most of the night.

In the letter, Udall writes that the "choreographed standing and clapping of one side of the room — while the other side sits — is unbecoming of a serious institution."

So far, 19 senators and a handful of House members, both Democrats and Republicans, have signed onto the plan. No other Minnesotan has signaled support thus far.

The State of the Union is scheduled for Tuesday, Jan. 25.