Washington: Democrats will retain control over the US Senate, after winning in closely-watched races in Massachusetts, Indiana and Virginia.
Republicans have, however, maintained their control of the House.
The division in control of the two houses of Congress has led to partisan battles and legislative gridlock since the last elections in 2010.
Democrats had a 53-47 majority in the outgoing Senate, while Republicans held a 242-193 advantage in the House.
In the fiercely-contested race for the 33 Senate seats up for ballot, Republicans have held seats in Texas, Tennessee and Mississippi, the BBC reports.
The two right-wing candidates who made controversial remarks about rape were also defeated.
In Massachusetts, Democrat Elizabeth Warren took the Senate seat once held by liberal icon Edward Kennedy, who died in 2009.
She unseated Scott Brown, who won Massachusetts for the Republicans after Kennedy’s death.
According to the report, Democratic incumbent Claire McCaskill had been considered vulnerable until Republican Todd Akin said that women's bodies had ways of avoiding pregnancy in what he termed "legitimate rape".
And Republican Richard Mourdock, who said in a debate that pregnancy resulting from rape was ‘something God intended’, was defeated in Indiana.
In Virginia, Democrat Tim Kaine defeated Republican George Allen. Both men are former state governors.
In Connecticut, Democrat Christopher Murphy replaces Senator Joe Lieberman, Al Gore's running mate in his ill-fated 2000 presidential bid, the report added.