Rep. Nancy Pelosi (D-Calif.) was sworn in today as the first woman speaker of the House in U.S. history, as Democrats formally took control of Congress for the first time in a dozen years and immediately set their sights on quick passage of ethics legislation.

Pelosi, 66, took the oath of office at 2:30 p.m. EST after winning election as speaker in a straight party-line vote that reflected the Democrats' 233-202 House majority in the new 110th Congress. Rep. John A. Boehner (R-Ohio) became House minority leader.

Before taking the oath from Rep. John Dingell (D-Mich.), the longest-serving House member, Pelosi pledged in a speech to work in bipartisan fashion toward ending the war in Iraq, reining in deficit spending and raising ethical standards among lawmakers, among other goals.

Hailing her election to the speakership as a "historic moment for the women of America," Pelosi declared, "For our daughters and granddaughters, today we have broken the marble ceiling. . . . Now the sky is the limit. Anything is possible."

Boehner, who introduced Pelosi, said her election "marks an occasion that I think the founding fathers would view approvingly." Regardless of party affiliation, the Ohio Republican said, "today is a cause for celebration."

However, it did not take long for a note of partisanship to emerge, as a New Jersey Democrat raised a point of parliamentary inquiry moments after Pelosi took her oath to note that the election of one Florida Republican to a House seat is being contested in court and in Congress. Pelosi said the oath-taking that she then administered to the assembled lawmakers was "entirely without prejudice" to the final outcome of that challenge.

Earlier, Pelosi pledged to stick to an ambitious plan to push through legislation on several fronts during the first 100 hours the House is in session. Besides cracking down on what they have called a "culture of corruption" in Washington, House Democrats plan to pass bills raising the minimum wage and promoting stem cell research, among other measures.

In the Senate, where Harry M. Reid (D-Nev.) took over as the new majority leader, lawmakers from both parties attended a joint caucus this morning in an effort to set a bipartisan tone before the official opening of the 110th Congress. Reid's office said the meeting was "an opportunity to break through the partisan gridlock that has gripped Washington in recent years."

As the midday oath-taking got underway in the Senate, Vice President Cheney began swearing in senators in groups of four on the Senate floor. Among the first to take their oaths was Sen. Robert C. Byrd (D-W.Va.), 89, who will serve as president pro tempore of the Senate, making him third in the line of succession to the presidency.

Also sworn in by Cheney was Sen. Hillary Rodham Clinton (D-N.Y.), a prospective presidential candidate in the 2008 elections.

In the House, which also convened at noon, Rep. Rahm Emanuel (D-Ill.), chairman of the body's Democratic Caucus, introduced Pelosi as the party's candidate for speaker of the House. Rep. Adam H. Putnam (R-Fla.), chairman of the House Republican Conference, formally nominated Boehner for the same position. The ensuing roll-call vote was a formality.

As she awaited the results of the lengthy roll call, Pelosi held her youngest grandchild in her arms while greeting lawmakers who came up to congratulate her. After the vote, Democrats gave her a sustained ovation.

In the Senate, Democrats hold a 51-49 edge, including two independents who caucus with the party.

Among those in attendance for the oath-taking was former president Bill Clinton, who startled reporters when he swept through the Senate press gallery on his way to the men's room, Washington Post staff writer Lois Romano reported.

Looking pleased when reporters jumped up to follow him to the men's room door, an ebullient Clinton quipped, "I came here to apply for a job -- you got an opening?" After emerging from the restroom, he said he was on hand for "Hillary's swearing in," but he demurred when queried about when she would announce her candidacy for president.

"Ask her," said Clinton, who then acknowledged that he liked the idea of becoming first spouse. "This is definitely a great day" for the Senate, he said in response to another question.

After this morning's joint Democratic-Republican caucus in the Old Senate Chamber, Reid, 67, said he and Sen. Mitch McConnell (R-Ky.), the new Senate minority leader, "believe this is a new day in Washington." He said the first order of business would be bipartisan legislation to reform lobbying practices, a bill he said was "long overdue and absolutely necessary."

Next will be legislation to raise the minimum wage, he said, "and Senator McConnell and I are working to see if we can offer something together on that issue."

McConnell, 64, said the joint caucus "was a chance for many of our members to express some of their quiet frustrations, that we get past the level of partisanship that we've witnessed in recent years and develop stronger personal relationships."

After being introduced as the new House speaker this afternoon, Pelosi said, "I accept this gavel in the spirit of partnership, not partisanship, and I look forward to working . . . with you, Mr. Boehner, and the Republicans in the Congress, for the good of the American people." She called on lawmakers to build a future worthy of the sacrifices of U.S. service members, and she paid tribute to former president Gerald R. Ford, a longtime Republican congressman from Michigan who died last week.

In a speech that was part homage to America's women, Pelosi also thanked her family for "the confidence they gave me to go from the kitchen to the Congress."

Saying that the November elections had shown the need for "a new direction" in Iraq, the San Francisco Democrat called on President Bush to provide one when he addresses the nation on the issue, possibly next week.

"The American people rejected an open-ended obligation to a war without end," she said. "It is the responsibility of the president to articulate a new plan for Iraq that makes it clear to the Iraqis that they must defend their own streets and their own security, a plan that promotes stability in the region and a plan that allows us to responsibly redeploy our troops."

Pelosi also vowed that "after years of historic deficits," the new Congress would "commit itself to a higher standard: Pay as you go; no new deficit spending." She added, "Our new America will provide unlimited opportunity for future generations, not burden them with mountains of debt."

But the first order of business, she said, "is passing the toughest congressional ethics reform in history."

Before formally opening the first session of the new House, Pelosi invited the children in attendance, including her own grandchildren, to come up to the podium and touch the speaker's gavel.

"For these children, our children and for all of America's children, the House will come to order," she said as she pounded the gavel as speaker for the first time.

At a swearing-in ceremony for officers of the Congressional Black Caucus this morning, Pelosi, an Italian American mother of five and grandmother of six, pledged to lead the House in a "new direction" toward ending child poverty, strengthening the middle class and improving access to education and health care.

"We are going to make children the centerpiece of this Congress," she said.

Pelosi also vowed to work for full representation in Congress for the District of Columbia, which currently has a delegate in the House who can participate in debate and vote in committee but cannot vote on the House floor.

"This is where so much of the energy for change will begin, as we go through . . . our first 100 hours," Pelosi told the Congressional Black Caucus. "One hundred hours to make this the most honest and open Congress in history; 100 hours to raise the minimum wage, to reduce the cost of college for our students, to make health care more affordable, to make our country safer; 100 hours to promote stem cell research; 100 hours to do that all in a fiscally sound way that does not heap mountains of debt onto future generations, but instead gives future generations what our country is all about: opportunity."

Following the swearing-in ceremony on the House floor, Pelosi and other Democrats planned to celebrate this evening at a concert in Washington's National Building Museum. The $1,000-a-ticket event, hosted by the Democratic Congressional Campaign Committee, features performances by such singers as Tony Bennett and Carole King.

In their first act as the House majority, Democrats said they would introduce a package of rule changes to ban gifts and trips from lobbyists, restrict privately funded junkets and begin to sever the cozy relations between lobbyists and lawmakers that scandalized the last Congress, Washington Post staff writers Jonathan Weisman and Jeffrey H. Birnbaum reported.{vbar}

But a number of loopholes in the proposal have led ethics watchdogs to complain that lobbying groups would still be able to finance lawmakers' travel as long as those funds were channeled through a nonprofit foundation. In addition, almost all banned perks would still be permitted if given in the context of a campaign fundraiser.

The changes would bar House members or employees from knowingly accepting gifts or travel from a registered lobbyist, foreign agent or lobbyist's client, and lawmakers would no longer be allowed to fly on corporate jets. Congressional travel financed by outside groups would have to be preapproved by the ethics committee and immediately disclosed to the public.

In another set of changes to be voted on in the House tomorrow, lawmakers' pet projects -- known as "earmarks" -- would have to be claimed by their sponsors, who would have to specify who benefits. That measure would apply not only to spending bills but also to tax measures and policy legislation, which in recent years have been larded with narrowly targeted provisions.