By Thomas Ferraro and David Lawder
WASHINGTON (Reuters) - U.S. lawmakers in both parties on Wednesday re-elected most of their leaders for the upcoming new Congress while Nancy Pelosi ended some suspense by announcing she would seek to remain the top Democrat in the House of Representatives.
In the Senate, Republicans re-elected Mitch McConnell as their leader, notwithstanding his failure to achieve two top goals in last week's national elections, defeating President Barack Obama and gaining a Republican majority in the Senate.
Senator John Cornyn, who headed the Senate Republican Campaign Committee, ended up with a promotion, getting elected without opposition to replace retiring Senator Jon Kyl of Arizona as the chamber's minority whip.
House Speaker John Boehner was re-elected as expected to lead his party in the House, which means the full House will re-elect him as speaker in January.
Eric Cantor was re-elected to the post of House Republican leader, and Cathy McMorris Rodgers, a rising political star and currently vice chair of the House Republican Conference, defeated Tom Price to head the conference.
McMorris Rodgers, the highest ranking woman in Republican leadership, served as House liaison for the party's unsuccessful presidential nominee, Mitt Romney.
The 112th Congress, now in a post-election lame duck session, will become the 113th Congress in January before Obama is inaugurated for his second term. The leaders chosen on Wednesday are to serve through 2014.
Pelosi, like McConnell, fell short of her election ambitions last week as Republicans maintained their hold on the U.S. House of Representatives.
But she ended months of speculation about whether she would seek another two-year term as House Democratic leader, saying she had decided in the past 24 hours after consulting with colleagues and family.
First elected as the top House Democrat on November 2002, Pelosi's reign has included four years as the chamber's first and only woman speaker. It ended in 2011 after Republicans won control of the House and made John Boehner speaker.
As of early Wednesday, Pelosi's decision on whether to seek another term as Democratic leader remained a secret with top aides saying it remained unclear what she would do.
She first told fellow House Democrats at a private meeting and then publicly announced it at a news conference.
"Being actively involved in politics at this level is really insatiable," said Pelosi.
Many Democrats had urged her to stay and she seems certain to win the job in House Democratic leadership elections set for November 29.
Pelosi bristled when asked by a reporter about the top three Democratic leadership spots being held by members in their 70s, and if that prevents an injection of younger blood into the ranks.
Amid hisses and boos from fellow House Democratic women, Pelosi asked if anyone had posed that question to McConnell, 70. None did at his news conference.
Without opposition, McConnell won reelection as the top Senate Republican despite having failed to win back the chamber from Democrats, who have held it since 2007.
McConnell's bad election day drew fire last week from some on the political right, who have complained that he is not conservative enough.
Senator Marco Rubio, a favorite of the anti-Washington Tea Party movement, stepped forward, however, to formally nominate McConnell for another two-year term as the party's Senate leader.
"Mitch unifies all of us, regardless of philosophy or what part of the country we come from," Rubio told a closed-door meeting of his colleagues, a Rubio aide said.
"He's the smartest political mind around and a great listener," Rubio added. "Mitch cares about is whether we succeed as a conference and as a country."
Senate Democrats re-elected their leadership team, which includes Harry Reid as leader and Dick Durbin as his assistant leader.
Reid said that he would like to reduce scores of procedural roadblocks, led by McConnell, that have blocked much of Obama's agenda the past two years.
Reid has said he wants to make sure that the Senate can easily begin consideration of a bill, but would still allow Republicans to require the support of 60 of the chamber's 100 members to end debate and move to a vote on passage.
"We're going to make an attempt to change the rules," said Reid. "We are working to make sure we have the votes to do it."
At the start of a new Congress, Reid would need just a simply majority. But some Democrats may oppose a rules change, knowing that eventually they will be in the minority and may regret a rule change.
(Reporting By Thomas Ferraro; Additional reporting by Richard Cowan, Kim Dixon and Rachelle Younglai; Editing by Fred Barbash, Doina Chiacu and Tim Dobbyn)