On February 7, 2006, he announced that he would seek the Democratic nomination for the 2006 Senate race against incumbent Virginia Senator George Allen.

In the Democratic primary on June 13, 2006, Webb faced longtime businessman and lobbyist Harris Miller.
Webb won with 53.5% of the vote, in a race with low turnout.
On January 4, 2007, Webb was sworn into the 110th U.S. Senate, accompanied by Sen. John Warner, R-Va.,
a fellow former Secretary of the Navy; and former Virginia Democratic Sen. Chuck Robb, who held the same seat before losing to Allen.

On November 15, 2006, Senate majority-leader-in-waiting Harry Reid assigned Webb to three committees: the committees on Foreign Relations, Veterans' Affairs, and Armed Services.

On January 23, 2007, Webb delivered the Democratic response to the President's State of the Union address, focusing on the economy and Iraq.
 Webb's speech drew positive reviews, and was regarded as one of the stronger State of the Union responses in recent memory.
Webb, a decorated war veteran, spoke of his family’s military past, his own passionate attachment to the military, and the way in which previous presidents had always attempted to ensure that all precautions had been taken when sending young Americans into harm's way.

On August 14, 2009 Webb visited Myanmar (Burma), seeing its junta's leader, Gen. Than Shwe, and also the pro-democracy leader Aung San Suu Kyi, who was under house arrest.
During Webb's visit with Than Shwe, Webb negotiated the release and deportation of an imprisoned American, John Yettaw.

On February 9, 2011, Webb announced that he would not run for re-election of his Senate seat in 2012.
On February 7, 2006, he announced that he would seek the Democratic nomination for the 2006 Senate race against incumbent Virginia Senator George Allen.
In the Democratic primary on June 13, 2006, Webb faced longtime businessman and lobbyist Harris Miller. Webb won with 53.5% of the vote, in a race with low turnout. On January 4, 2007, Webb was sworn into the 110th U.S. Senate, accompanied by Sen. John Warner, R-Va., a fellow former Secretary of the Navy; and former Virginia Democratic Sen. Chuck Robb, who held the same seat before losing to Allen.
On November 15, 2006, Senate majority-leader-in-waiting Harry Reid assigned Webb to three committees: the committees on Foreign Relations, Veterans' Affairs, and Armed Services.
On January 23, 2007, Webb delivered the Democratic response to the President's State of the Union address, focusing on the economy and Iraq.  Webb's speech drew positive reviews, and was regarded as one of the stronger State of the Union responses in recent memory. Webb, a decorated war veteran, spoke of his family’s military past, his own passionate attachment to the military, and the way in which previous presidents had always attempted to ensure that all precautions had been taken when sending young Americans into harm's way.
On August 14, 2009 Webb visited Myanmar (Burma), seeing its junta's leader, Gen. Than Shwe, and also the pro-democracy leader Aung San Suu Kyi, who was under house arrest. During Webb's visit with Than Shwe, Webb negotiated the release and deportation of an imprisoned American, John Yettaw.
On February 9, 2011, Webb announced that he would not run for re-election of his Senate seat in 2012.
Jim Webb