Republicans elect Mitch McConnell as US Senate leader

Republican lawmakers re-elected Mitch McConnell as their leader in the US Senate on Wednesday, ensuring him the powerful role of majority leader in the new Congress that begins in January.

Meanwhile, President Barack Obama's Democrats, who lost control of the Senate with their crushing defeat in this month's mid-term elections, re-elected their own leader in the chamber.

McConnell, the 72-year-old senior senator from Kentucky, will take over from current Senate Majority Leader Harry Reid at the start of the new congressional session on January 3.

The Senate Republican leadership team, with Senator Mitch McConnell (C), at the US Capitol after a leadership election on November 13, 2014 in Washington, DC ©Alex Wong (Getty/AFP)

"We are eager to work towards bipartisan agreements and to implement real legislative accomplishments," McConnell said.

But shortly afterwards he blasted Obama for several unilateral steps the president has taken since the midterms.

"I had maybe naively hoped the president would look at the results of the election and decide to come to the political center and do some business with us," McConnell told reporters.

"I still hope he does at some point, but the early signs are not good."

McConnell has coveted the majority leader role for decades.

The position will put him in control of the legislative agenda of the 100-member Senate and require close coordination with the top Republican in Congress's lower chamber, House Speaker John Boehner, who was also re-elected Thursday to lead his caucus.

Senate Democrats, meanwhile, re-elected Reid as their leader, although not without some opposition.

At least two Democrats, Senators Claire McCaskill and Joe Manchin, voted against Reid, saying they wanted to chart a new course of bipartisan cooperation.

"There's a lot of us who feel that it's time for us to not mimic what the Republicans did, but rise above that and try to work together," McCaskill told reporters.

Reid, 74, has been majority leader since his party won the Senate eight years ago, but must now trade places with McConnell.

He insisted he was not going to stall Republican legislative action, following a particularly partisan and bitter two years.

"This is not get-even time. I do not intend to run the Democratic caucus like the Republican caucus has been running the minority," he said, referring to the heightened number of blocking procedures known as filibusters used while McConnell has been minority leader.

Reid signalled a potential shift by announcing he was creating a special leadership post in the Democratic caucus for first-term Senator Elizabeth Warren.

The former Harvard professor, a populist progressive, will be a strategic Democratic policy adviser, helping to shape the party's policy positions and priorities.

- Credible challenge -

Warren will also serve as a liaison to progressive groups to ensure they have a voice in leadership meetings and discussions, according to a source familiar with the role.

"Wall Street is doing very well, CEOs are bringing in millions more, and families all across this country are struggling. We have to make this government work for the American people," she said.

Progressives see Warren as posing a credible challenge from the left against Hillary Clinton should the former secretary of state choose to seek the White House in 2016.

Republicans re-elected John Cornyn as Senate Republican whip and John Thune as Senate Republican Conference chairman.

In a secret ballot, they also chose Senator Roger Wicker of Mississippi to helm the National Republican Senatorial Committee.

As head of the party's campaign arm, Wicker will oversee campaigns in the run up to the 2016 polls, when Republicans will be defending 24 of the 34 Senate seats up for election.

Senator John Tester, a red-state Democrat from Montana, was chosen to lead the Democratic Senatorial Campaign Committee into 2016.

US Senate Majority Leader Senator Harry Reid speaks to members of the media after a Democratic Senate leadership election on November 13, 2014 in Washington, DC ©Alex Wong (Getty/AFP)