Reid: 'It's time to put aside this political theater' on Hagel votes

The move means Hagel will not be confirmed until at least after the Presidents Day recess and he will not be able to travel to a NATO meeting next week about the war in Afghanistan.

Retiring Defense Secretary Leon Panetta has pledged to stay on duty until Hagel is confirmed.

This is the first time a nominee for the top Pentagon job has been subject to a filibuster, a fact that highlights how contentious Hagel's nomination has become. While Hagel served as a Republican senator just more than four years ago, his views on Iran, Iraq and Israel led to a fiery debate over his nomination. Hagel went through a rough confirmation hearing last week, enduring tough questions from Republican senators and turning in an uneven performance.

Since then, Republicans have demanded more information about speeches the nominee gave and his compensation for them. Sen. Ted Cruz (R-Texas) at a hearing this week suggested the speeches were given to extreme or radical groups, a statement some Democrats have criticized.

Senate Majority Leader Harry Reid (D-Nev.) stepped up pressure Thursday for Republicans to allow an up-or-down vote, arguing it would leave the U.S. without a Defense secretary.

“We, at 12 o’clock today, do not have a secretary of Defense,” Reid said on the Senate floor Thursday morning. “It is shocking that our Republicans colleagues would leave our nation without a secretary of Defense with all the things going on and when we’re in a war.”

Reid has filed a motion to end debate on Hagel's nomination and move to a final vote. The vote to end debate is scheduled for Friday.

For more on Reid's comments, click here.