Obama admits Republicans had 'a good night'

President Barack Obama has conceded that the Republican party has had a "good night" after they secured a majority in the US Senate in last night's midterm elections.

He said that the message from last night was that voters want to see the Washington gridlock eased.

Watch Obama's press conference at the White House:

Read: Republicans resurgent: Tough times ahead for Obama

As well as claiming a victory in the Senate, Republicans were expected to extend their lead in the House of Representatives to 246 seats to 189, give or take six seats.

NBC News' political director Chuck Todd says such a lead would make it unlikely that the Democrats could retake the House before the year 2022.

A Republican majority in the Senate could make President Barack Obama's remaining time in office much more difficult, as Kate Fisher reports from Washington:

The Empire State Building in New York has been lit up in red after Republicans claimed a majority of seats in the Senate in Tuesday's Midterm Elections.

Democratic Senate leader Harry Reid has called his Republican counterpart Mitch McConnell to congratulate him on becoming the new majority leader in the U.S. Senate.

In a statement Senator Reid said: "The message from voters is clear: they want us to work together. I look forward to working with Senator McConnell to get things done for the middle class."

Read: Republicans to hold at least 52 Senate seats

The Republicans will hold a comfortable majority over the Democrats in the US Senate according to projections from Reuters and pollsters Ipsos.

Both give the party at least 52 of the chamber's 100 seats after Tuesday's mid-term elections.

Analysis: Why the midterm results are crucial for Barack Obama

The White House press secretary has tweeted that President Obama has spoken to Congressional candidates from both parties as results come in from the mid-term elections.

Josh Earnest said there would be "more details" to come later today.

Analysis: Why the midterm results are crucial for Barack Obama

The Republicans are set to take control of the US Senate after being projected to take a seat in Iowa from the Democrats.

Iraq war veteran Joni Ernst is expected to triumph over Democrat Bruce Braley.

She will become the first woman to ever represent the state in the US Senate.

Analysis: Why the midterm results are crucial for Barack Obama