Election results were still coming in when the Democrats picked up the necessary 15 seats to reclaim control of the House for the first time since 1994.
President Bush reportedly watched election returns at the White House, where the tone was "businesslike," administration spokesman Tony Snow said, according to the Associated Press. The president planned to address the nation Wednesday afternoon.
Meanwhile, Democratic leaders were jubilant at the end of Tuesday night.
"The old era of irresponsibility is over, and the new era of real reform has just begun," said Rep. Rahm Emanuel, D-Ill., during a speech at the Democratic national headquarters in Washington, D.C. "You have given us a chance to turn this country around, and we'll give you the government that no longer lets you down."
Democratic National Committee Chairman Howard Dean told CNN, "There's not a lot we can do to actually force the president to leave Iraq, but ultimately we can have some influence and I think you'll see certainly an attempt by Democrats to change the direction."
The Democratic win means Rep. Nancy Pelosi, D-Calif., will take over as House speaker, which would put her third in line to the presidency, behind the vice president.
"Democrats support change," Pelosi said at a victory party in Washington. "Democrats propose a new direction for all Americans, not just the privileged few," she said, according to the Associated Press.
Pelosi has said she will not try to end U.S. funding of the Iraq war, will pressure Bush to shift course, begin a phased redeployment of U.S. troops and require Iraqis to take greater responsibility for their own nation.
The news came after President Bush spent the last five days of the campaign trying to help Republican candidates in 10 states.
"The president has got a very active agenda for the next two years and you're going to need both parties. There has to be a calculated decision by the Democrats," Snow said, according to AP.
Ken Mehlman, head of the Republican National Committee, told reporters Wednesday morning that the election would force members of Congress to forge coalitions if legislative work is to get done.
"I think that, fundamentally, we need to put coalitions together that make sure that we don't have Iraq turning into another Afghanistan, and we work together on behalf of things, on behalf of the American people. I think that's critical," Mehlman told NBC's Chris Mathews.
The White House announced that President Bush would have a press conference Wednesday afternoon to map out his post-election goals.
