Postpublished at 06:04 Greenwich Mean Time 5 November 2014
We will continue to cover the story with analysis and more reaction on bbc.com/news
The Republican Party has taken control of the Senate by picking up at least six seats from the Democrats
They have also strengthened their grip on the House of Representatives
Ballot initiatives expanding marijuana use and increasing minimum wage passed in some states
The economy, government dysfunction and President Obama's unpopularity were key issues
Tom Geoghegan, Debbie Siegelbaum, David Walker, Taylor Brown, Kate Dailey, David Botti, Helier Cheung, Victoria Park and Alison Daye
We will continue to cover the story with analysis and more reaction on bbc.com/news
This concludes our coverage of the US mid-term elections on a night of major wins for Republicans in the Senate and some surprising upsets in state governor races.
Most polls in Alaska are now closed. The last Senate race of the night will be determined there.
Democrat John Barrow had held his Georgia Congressional seat since 2004, but his defeat tonight marks the end of an era for his party's Southern history.
But in an editorial on Foxnews.com, external, Douglas Schoen says Republicans "got everything they wanted Tuesday night - and more".
He added: "This election represents a complete rejection of the president, his agenda and his leadership".
The US media is digesting the news of a resounding night for the Republicans.
"Virtually every Republican candidate campaigned on only one thing: what they called the failure of President Obama," says a New York Times editorial, external, which condemns what it calls a negative Republican campaign.
Suzanne Kianpour
BBC News, Washington
tweets, external: "Only 3 of 10 Senate candidates that Hillary Clinton supported won tonight. (Mary Landrieu TBD)"
Just to recap, the Republicans have swept to power in the Senate and strengthened their grip on the House, meaning they control both chambers of Congress for the first time since 2006.
Capitalising on voter dissatisfaction with the direction of the country, and the unpopularity of President Obama, they picked up seats in West Virginia, Montana, South Dakota, Colorado, North Carolina, Iowa and Arkansas.
This years mid-term election resulted in some history being made at the national and state levels.
"We are humbled by the responsibility the American people have placed with us, but this is not a time for celebration," House Speaker John Boehner says in a statement.
"Americans can expect the new Congress to debate and vote soon on the many commonsense jobs and energy bills that passed the Republican-led House in recent years with bipartisan support but were never even brought to a vote by the outgoing Senate majority, as well as solutions offered by Senate Republicans that were denied consideration."
Former Democratic governor of New Mexico, Bill Richardson, says Democrats have been let down today by poor turnout in key Latino states such as Colorado, Florida and Arizona. He's been telling BBC World Service that Latinos are upset over President Obama's slow progress on immigration reform.
Matt Viser
Boston Globe
tweets, external "Obama relationship with new Senate Majority Leader Mitch McConnell is nonexistent. He once called him "Mike." They've met individually twice."
Supporters of Senator-elect Joni Ernst cheer as results come in
There was one spot of bad news for Republicans on an otherwise successful night - incumbent governor Tom Corbett has lost to Democrat Tom Wolf in Pennsylvania. But Maryland Lt Governor Anthony Brown is in trouble in his race for the governor's seat in normally Democrat-safe Maryland.
Anthony Zurcher
BBC News
Oregon's ballot measure to legalise the sale and possession of marijuana has passed. The state joins the District of Columbia in approving pot-legalisation initiatives. Although a majority of Florida voters also voted in favour of legalisation today, it did not break the 60% support level necessary for passage there.
The Huffington Post's Hunter Stuart has an interesting look , externalat what Oregon's move means for neighbouring Washington state, which passed its own legalisation two years ago, including what significantly lower taxes on the drug in Oregon means.
David Frum
The Atlantic
tweets, external: "Is tonight's takeaway that Republicans do great when voter turnout drops below 38%?"
The Vermont governor's race is close, but neither Governor Peter Shumlin nor challenger Scott Milne gained more than 50% of the vote. But there is no run-off - and the Vermont legislature will now pick the governor.
We've distilled the night so far into a picture gallery. Expect a few smiling Republicans.
Colorado GOP Governor Bill Owens told BBC World Service Republican gains in the midterms are "fairly sweeping" and a denunciation of President Obama's agenda. He predicted Republican control of both Houses of Congress would put American politics back on a more moderate path.
Democrat Tom Udall wins re-election to his Senate seat in New Mexico.