Jan. 4 (Bloomberg) -- Nancy Pelosi was elected the first female speaker of the House of Representatives as Democrats took control of both chambers of Congress for the first time since 1994.

``It's a historic moment for the Congress and a historic moment for the women of America,'' Pelosi told lawmakers in the House chamber. ``It is a moment for which we have waiting for over 200 years.''

In the Senate, Majority Leader Harry Reid, a Nevada Democrat, vowed a longer work week for lawmakers and more cooperation with Republicans.

``The American people are expecting positive results from this the 110th Congress, not more partisan rancor,'' Reid said. ``The voters want change.''

Pelosi won election as speaker by a party-line vote of 233- 202. She is taking office with two goals: becoming an effective counterweight to President George W. Bush, and proving that a woman can thrive at the summit of U.S. political power.

Pelosi's attacks on Bush while minority leader are credited by many Democrats with helping them win control of Congress for the first time since 1994. As speaker, she'll be dealing with a narrow majority and a president with veto power, making decisions about when to work with Bush and when to confront him.

Supreme Court, Cabinet

While women have served as Supreme Court justices, lawmakers and in senior Cabinet roles, none has ever led her party in political combat at this level. Her success at retiring the notion that women aren't qualified to manage the responsibilities of top leadership may affect others' aspirations, including New York Senator Hillary Rodham Clinton's possible bid for the White House in 2008.

``As people see Nancy Pelosi on the national stage, setting the agenda and leading the people's House, it helps to set the stage for Senator Clinton in her run for president, and indeed for other women who may want to run for Senate or run for governor,'' said Ellen Moran, executive director of EMILY's List, which raises political funds for Democratic women.

Pelosi, 66, said in remarks after her election that she is committed to working with Republicans on legislation.

``We have made history,'' she said. ``Now, let us make progress for the American people.''

Presidency

No woman has been as close to the presidency itself: The California congresswoman will be second in line, behind only Vice President Dick Cheney.

Over the past five years, Pelosi emerged as one of the top congressional critics of the war in Iraq. In 2002, she broke with then-Minority Leader Richard Gephardt of Missouri and led a bloc of Democrats who voted against the resolution authorizing the war. She was also one of the first members of Congress to question Bush's assertion that Iraq had weapons of mass destruction, a claim that was used to justify the March 2003 invasion and that later proved inaccurate.

She said today that in the 2006 midterm election ``the American people rejected an open-ended obligation to a war without end,'' and she called on Bush to develop a new plan for Iraq ``that allows us to responsibly redeploy our troops.''

Pelosi will have her first opportunity to spar with Bush over Iraq in February when the White House submits a request for more money for the war. Pelosi has warned that Democrats will attach conditions to the approval of further funds.

Unity

Pelosi, who was largely able to maintain House Democrats' unity and discipline when they were in the minority, may have a tougher job now that they are in power. Members have already defied her by rejecting Representative John Murtha of Pennsylvania, her choice for the No. 2 job of majority leader, in favor of Steny Hoyer of Maryland, the current No. 2.

At the same time, she will face the task of trying to push her agenda through a still closely divided House. Democrats will hold 233 seats in the new House, Republicans 202. Things are even tighter in the Senate, where Democrats hold only 51 of the 100 seats -- and one Democrat, Tim Johnson of South Dakota, remains hospitalized after brain surgery.

Bush, 60, vowed yesterday to cooperate with the Democrats - - even as he warned that he would oppose tax increases. ``Congress has changed,'' he said in remarks at the White House after a meeting with his Cabinet. ``Our obligations to the country haven't changed.''

Backsliding

House Republicans say Pelosi is already backsliding on promises to allow more open debate to the House floor. She indicated last month that she won't let Republicans try to amend key parts of Democrats' agenda, including legislation to raise the minimum wage to $7.25 an hour, curbing subsidies for oil and gas companies and reducing student-loan interest rates.

The new speaker is hardly a stranger to rough-and-tumble politics. Her father, Thomas D'Alesandro, was mayor of Baltimore and a congressman; a brother also served as Baltimore mayor.

Pelosi, who represents San Francisco, wasn't elected to Congress until 1987, when she was 47 and the youngest of her five children was in high school. She eventually rose to become the top Democrat on the intelligence committee and the appropriations subcommittee on foreign operations.

In 2001, she defeated Hoyer to become Democratic whip. She became minority leader -- the first woman to lead a party in Congress -- after Gephardt stepped down late the next year.

Record Numbers

Her elevation to speaker comes during a year when record numbers of women will hold seats in Congress -- 16 in the Senate and 71 in the House. Moran said the Washington-based EMILY's List group sees an opportunity to raise record levels of cash in 2008 after raising $45 million in 2006.

Susan MacManus, a political science professor at the University of South Florida in Tampa, said the significance of Pelosi's new role goes beyond issues of partisanship, showing that women can make decisions on the weightiest issues of government.

Even though two of the last three secretaries of state are women, ``quietly, people are thinking maybe women can't handle the stresses of war and international negotiations,'' MacManus said. ``Pelosi is going to be right there in the middle of military and foreign policy. Her dealings on these issues are absolutely essential to the success of other women.''

To contact the reporter on this story: Laura Litvan in Washington at llitvan@bloomberg.net

Last Updated: January 4, 2007 15:41 EST