WASHINGTON (Reuters) - Speaker of the House of Representatives Nancy Pelosi ended speculation that she may quietly step aside after her Democrats lost midterm elections, announcing on Friday she will run for minority leader in the new Republican-led chamber next year.
Pelosi made the announcement via her Twitter account, saying, "Driven by the urgency of creating jobs" and protecting healthcare, Wall Street reform and Social Security and Medicare, "I am running" for Democratic leader.
In the wake of Republicans winning control of the House from Democrats in the midterm congressional elections on Tuesday, Pelosi may face a challenger -- though none have yet surfaced.
House Democrats, particularly Pelosi's fellow liberals, are expected to rally behind their embattled 70-year-old leader, who in 2007 became the chamber's first woman speaker and is a close ally of President Barack Obama.
House Democratic Leader Steny Hoyer, the party's No. 2 in the chamber, had already said he would not challenge Pelosi if she decided to seek the post.
Republicans won the House in a landslide, promising to slam the brakes on Obama's agenda that Pelosi pushed through the House the past two years, including an overhaul of the U.S. healthcare system and a crackdown on Wall Street.
The White House declined comment on the leadership process. "As the president has said before, he appreciates the work of the speaker and the entire House Democratic leadership team who have been great partners in moving the country forward," a spokesman said.
There had been widespread speculation that Pelosi, who Republicans made their top election-year target, might step away from House Democratic leadership or even resign from Congress.
While polls show less than one in three Americans approve of the powerful yet often polarizing Pelosi, she won re-election on Tuesday to a 13th term from her liberal California district with 80 percent of the vote.
Pelosi, in a letter to fellow House Democrats, wrote that she intends to stay and fight to protect their legislative achievements.
"Our work is far from finished. As a result of Tuesday's election, the role of Democrats in the 112th Congress will change, but our commitment to serving the American people will not," Pelosi wrote.
"We have no intention of allowing our great achievements to be rolled back. It is my hope that we can work in a bipartisan way to create jobs and strengthen the middle class," Pelosi added.
Pelosi declared her candidacy after conferring with fellow House Democrats. Several members said they would not support her, but many urged her to run.
"The fact is, Nancy Pelosi is the single most effective member of Congress, period," said Democratic Representative George Miller, a longtime ally.
Larry Sabato, a political science professor at the University of Virginia, noted that Pelosi has been described as the most powerful House speaker since Sam Rayburn, the tough Texan who presided over the chamber more than a half-century ago.
"Now she wants to imitate Rayburn -- stay as minority leader after losing" the speakership, Sabato said.
Representative John Yarmuth, a Kentucky Democrat, made an about-face and backed Pelosi as minority leader, a day after saying, "I don't think she's the right leader to take us forward."
Yarmuth said on Thursday he would prefer Hoyer as minority leader, but on Friday said he would vote for Pelosi, citing her ability to "build consensus" in a diverse Democratic caucus and advance policies that "improve the lives of all Americans."
But Representative Dan Boren, a conservative Oklahoma Democrat, remained opposed to Pelosi. He told Fox News that he would support someone more conservative. "People are so mad about the extremists in both parties," Boren said.
While it was unclear who, if anyone, may challenge Pelosi, Representative Heath Shuler, a conservative North Carolina Democrat, said during the campaign that he might try.
Hoyer, a moderate, had been seen as the likely new House minority leader if Pelosi decided not to seek the post.
Within minutes after Pelosi announced she wanted the job, Hoyer's office said he may run for the No. 2 Democratic position in the new Republican House, minority whip.
But Hoyer would face a fight. The current House Democratic Whip, James Clyburn, announced on Friday that he intends to run again for the job.
Clyburn offered Democrats hope, noting that in both 1946 and 1952, they lost control of the House, but quickly regrouped and won back the chamber two years later.
Representative Chris Van Hollen is the only member of House Democratic leadership to say he will step down. He plans to surrender his post as head of the House Democratic campaign committee as soon as any remaining undecided races are settled.
Additional reporting by Steve Holland; Editing by Eric Beech