05:14 GMT - More pot - US media project that Oregon will OK marijuana use. The move makes it the third state in which it will be legal to use the drug recreationally, catching up with Colorado and neighboring Washington.
Virginia Democratic Senator Mark Warner departs the stage after addressing an election night rally
05:06 GMT - Maryland surprise - In what would be a real upset, the overwhelmingly Democratic state of Maryland seems to be about to elect a Republican governor. Businessman Larry Hogan has a sizable lead over Lt. Governor Anthony Brown, who has been slammed for tax increases under the incumbent.
05:00 GMT - CALLING IT A NIGHT - We are closing our Live Report on the US elections.
Races are still undecided around the country, and final results from Alaska to Connecticut may not be known for days. But the big question has been answered. A Republican wave washed over the Senate, giving the GOP control of the upper chamber for the first time since President Barack Obama was elected.
The White House issued no reaction, but we can expect Obama to speak to reporters at some point on Wednesday and probably take questions. Obama retains some power through executive orders and the veto pen, but substantive governance will require cooperation. With majorities is both houses, the Republicans will determine the country's legislative agenda at least until the next presidential vote.
And so, with ballots from Tuesday's vote still being counted, talk over breakfast in Washington will turn to 2016.
04:40 GMT - Squeal - Joni Ernst's big win in Iowa makes her the first woman to represent the agricultural state in the Senate. The 44-year-old Army and National Guard veteran served in Kuwait in 2003 and 2004. One of her campaign ads, titled "Squeal," went viral for both friends and foes. She asserted her experience castrating hogs growing up gave her the experience needed to cut "pork" spending in Washington.
04:38 GMT - Harry Reid - Senate Majority Leader Harry Reid acknowledged his was not long for the job. He released a statement making the usual vow of bipartisanship.
"I'd like to congratulate Senator McConnell, who will be the new Senate Majority Leader. 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."
04:35 GMT - Youngest woman - A 30-year-old upstate New York Republican makes history by becoming the youngest woman elected to US Congress, shattering a record set before she was born. Elise Stefanik, a former White House aide to president George W. Bush, beat her Democrat challenger, film producer Aaron Woolf.
The last record was last set by former Democratic representative Elizabeth Holtzman in Brooklyn who won a seat in the House in 1972 when she was 31 years old and took her seat in 1973.
US media has dubbed Stefanik a rising star in her party. She currently works in her family's business, a distributor of hardwood plywoods with more than 1,000 customers.
04:32 GMT - Two more - Tight Senate races in North Carolina and Iowa both go for the Republicans, turning the map Republican red.
04:27 GMT - REPUBLICANS TAKE SENATE CONTROL - Both Fox News and CBS project that Republicans will take control of the US Senate.
04:22 GMT - Kansas seat stays red - Kansas also goes the Republicans' way, with veteran Senator Pat Roberts surviving a mighty battle with businessman Greg Orman, an independent who had the potential to play Senate kingmaker.
03:45 GMT - Rick Scott stays in Governor's mansion - In Florida, incumbent Republican Governor Rick Scott held off an insurgent charge from Charlie Crist. The famously tanned Crist is a former Republican governor who only took up the flag of the Democrats in 2012 in the middle of a losing Senate bid. That move helped Scott's well-funded campaign in efforts to paint Crist as a flip-flopper. Their acrimonious race veered off course amid such side issues as Crist's use of a fan at a debate.
03:41 GMT - No runoff in Georgia Senate race - Republicans are able to hold onto their seat from the state of Georgia, avoiding a runoff that could have dragged a result on for months. David Perdue beat Michelle Nunn, the daughter of a former senator who put on a strong challenge but came up short.
03:32 GMT - Smoke it if you've got it - According to a partial vote tally, voters have overwhelmingly supported making it legal to possess marijuana in the nation's capital. The vote is complicated by Congressional oversight of the city so even organizers of the initiative asked supporters not to take to the streets, joint in hand, to celebrate.
03:23 GMT - Colorado makes it five - For the first time since 2002, a Republican has won a statewide vote in Colorado. With Cory Gardner unseating Senator Mark Udall, the Republicans are only one seat away from the big prize, a majority in the US Senate.
03:18 GMT - Fourth pickup for the Republicans - The rural farming and ranching state of Montana has given the Republicans another new seat for a total of four. The party needs only two more to take control of the chamber.
03:11 GMT - A new George Bush - Another George Bush is elected to office. George Prescott Bush, know informally as "P," won his campaign to become Texas Land Commissioner. He comes from a long line of winning Bushes. His grandfather is none other than former president George H.W., his uncle is former president George W. and his father served as governor of Florida.
02:48 GMT - Runoff - Because of the state's complicated voting rules, Louisiana was almost destined for a runoff and it got one. The incumbent Democrat Mary Landrieu will face Republican Bill Cassidy in December.
02:43 GMT - Virginia tightens - The surprise close race of the night, the Senate battle between incumbent Mark Warner and Ed Gillespie tightens. With a full 91% of the votes counted, only 6,400 votes divide the two candidates. There are still votes to be counted in the overwhelmingly Democratic suburbs of Washington, but the tightness of the race is making for a nailbiter.
02:40 GMT - Aiken loses again - Former "American Idol" star Clay Aiken, running for the Democrats, loses in his attempt to unseat Republican incumbent Renee Ellmers in North Carolina.
He's been in second place before -- in 2003 Aiken lost to Idol competitor Ruben Studdard in the second season of the singing competition. Social media poked fun at the celebrity-turned-politician, tweeting quips like "Clay Aiken loses again," with a photo of Studdard.
02:28 GMT - Down to three - Republicans pick up another Senate seat and now need only three more to seize control. Mike Rounds beat Democrat Mark Weiland to take an open seat that had been held by a Democrat.
Republicans keep control of House, boost chances for Senate majority
02:14 GMT - Diversity - South Carolina voters send Republican Tim Scott to the US Senate, making him the first African-American candidate to win statewide office in the formerly Confederate state since just after the US Civil War. He has served in the Senate since 2013 when he was named to fill an empty seat by Governor Nikki Haley, but this is the first time he had to face voters to keep his job.
02:08 GMT - Shaheen - ABC and NBC project that Democrat Jeanne Shaheen's efforts to paint Scott Brown as a "carpetbagger," a traditional slur against someone moving to a new location to seek office, worked. She is projected to hold onto her seat.
01:51 GMT - More closings - We are waiting for polls to close in Arizona, Colorado, Louisiana, parts of Michigan, Minnesota, Nebraska, New Mexico, New York, parts of South Dakota and Texas as well as Wisconsin and Wyoming.
Of those, the Senate races in Louisiana and Colorado are the most anticipated.
01:44 GMT - Women lawmakers - According to the National Journal, Democrat Alma Adams's win in a special election for a House seat in North Carolina will bring the number of women in the chamber to 100 for the first time in US history.
01:35 GMT - Odds improve - Statistician and political seer Nate Silver tweets that the odds of the Republican party, dubbed the GOP, taking control of the Senate surge with Cotton's win.
"GOP odds up to 80% after Arkansas called for Cotton (R)".
01:28 GMT - Republican pickup - First term Congressman Tom Cotton, only 37 years old, defeats incumbent Democrat Mark Pryor in Arkansas to take another Senate seat for the Republicans.
01:19 GMT - Virginia surprise? - Pundits seem surprised that the Virginia Senate battle between former governor and incumbent Senator (and oft-floated vice presidential pick) Mark Warner and former Republican party operative Ed Gillespie is so competitive. Early results have insurgent Gillespie up 52 to 45, even with a Libertarian candidate in the mix, likely taking votes from Gillespie.
01:10 GMT - New Hampshire - As the polls close in New Hampshire, the battle between incumbent Democrat Jeanne Shaheen and Republican Scott Brown is too close to call.
If Brown's name sounds familiar it is because, in 2010, he famously stunned Massachusetts Democrats by winning the Senate seat the late Edward Kennedy had held for almost 50 years. Brown lost reelection and is now trying to find a new way into the Senate from neighboring New Hampshire.
01:04 GMT - Republicans keep House - As expected, the Republicans are projected to keep control of the US House of Representatives. The Senate remains in play.
Republicans pick up Senate seat in West Virginia, McConnell reelected
00:57 GMT - Turnout - Turnout is famously low for US midterm elections. In 2010, a paltry 37.8% of eligible voters went to the polls, compared to the still low 53.6% who voted in 2012.
But candidates are trying to eke out every vote they can muster. Democrat Kay Hagan, who is trying to win a Senate seat in North Carolina against Republican Thom Tillis, urged her supporters to endure any lines.
"If you're in line to vote at 7:30 PM today, you will be allowed to vote. Every vote counts, so stay in line: "
00:50 GMT - Kentucky love - Fellow Kentucky senator and much-rumored Republican presidential hopeful for 2016, Rand Paul, tweets his pleasure at McConnell's win.
"A big congratulations to @Team_Mitch on a decisive victory tonight! #kysen"
00:46 GMT - Extended hours? - NPR and CNN both report that Charlie Crist, Florida's Democratic nominee for governor, has filed an emergency motion seeking to extend hours in Broward County, citing “systemic breakdowns.”
00:39 GMT - The big batch - A new hour will bring the biggest batch of poll closings. Voting will end in Alabama, Delaware, Connecticut, Illinois, Maine, Maryland, Massachusetts, Mississippi, Missouri, New Jersey, Oklahoma, Pennsylvania and Tennessee. Polls will also close in most of Kansas, Michigan, New Hampshire and Texas and some of South Dakota, as well. Expect results to come in fast and furious, although most of the states are not home to hotly watched seats.
00:31 GMT - Republican pickup - Multiple US media outlets predict that the Republicans have picked up their first seat of the night, with Shelley Moore Capito handily beating Democrat Natalie Tennant in West Virginia.
00:27 GMT - More closings - Polls close in North Carolina, West Virginia and Ohio.
00:15 GMT - Senate control - While McConnell is surely pleased to have fought off Grimes, the big prize, the coveted position of Senate Majority Leader, will not be decided for hours. It is possible, if unlikely, that we won't know for months. The spot wields significant power, setting the agenda for the upper chamber, including deciding what bills come up for a vote.
Current Majority Leader Harry Reid is not up for reelection, but he stands to lose his standing, or even any leadership role, if his party gives up control.
00:06 GMT - Too close to call? - As expected in competitive Georgia, both CNN and CBS say the races for Senate and governor are too close to call.
00:03 GMT - McConnell WINS - US media project Mitch McConnell retains his Senate seat, fighting off an insurgent Alison Grimes.
00:00 GMT - Polls close - Polls close in Georgia, the rest of Kentucky and some of New Hampshire.
23:48 GMT - Georgia - But readers hoping for results in Georgia in the first few minutes might not want to hold their breath. Unless one candidate wins more than 50 percent of the vote, the state requires a runoff between the top two vote earners. That means results for both the governor and Senate could be delayed until December, or even January.
The Republican Senate candidate David Perdue is ahead in polls against Democrat Michelle Nunn, the daughter of former senator Sam Nunn, but if Libertarian Amanda Swafford sneaks off with enough votes to keep him from a majority, the two top candidates will meet again on January 6, after the new Congress is sworn in.
23:43 GMT - Countdown clocks - The TV news networks are all counting down the minutes until the first big batch of exit polls can be announced, at 0000 GMT, when the polls close in many East Coast states, including battlegrounds Kentucky and Georgia. Polls will close in parts of New Hampshire, too.
23:31 GMT - Kanye - The vote draws the attention of politicians and celebrities alike. US rapper, and Kim Kardashian spouse, Kanye West, tweeted his support for the Democratic ticket. "The midterms are extremely important," he says. One minute later he adds, "I know it’s last minute, but if you haven’t voted, please vote today."
23:23 GMT - Kentucky - Mitch McConnell has served in the Senate since 1985 and as Minority Leader since 2007. He has a natural advantage as the incumbent, but has been susceptible to charges he is too close to Washington and too far from his Kentucky roots. The polls showed his battle with Grimes surprisingly close, but she took a hit for seeming scripted on the campaign trail. Very, very early results are showing McConnell with a big lead, but it is much too soon to draw any conclusions.
23:11 GMT - First polls close - Polls close in parts of Indiana and Kentucky, which is home to one of tonight's closely watched Senate seats. Republican Minority Leader Mitch McConnell, who desperately hopes to become Majority Leader, first must fight to hold onto his seat. He is facing a respectable challenge from Alison Grimes, a young Democrat who he has worked hard to tie to the unpopular President Barack Obama.
23:00 GMT - WELCOME to AFP's Live Report on the US elections - All 435 seats in the House of Representatives are up for a vote, but only 36 of the 100 Senate seats. A full 36 of the 50 states are voting for governor.
But all these numbers really come down to 10. That is the number of competitive Senate races that are in play and may flip from one party to the other. If the Republicans gain six seats, they will gain control of the upper chamber and have the chance to set the political tone for the next two years.
Today's vote is called a "midterm" because it comes in the middle of a four-year presidential term. Historically, the results are bad for the president's party. After his Democrats lost a staggering 63 seats in the House of Representatives to the Republicans in 2010 Obama famously called the shift a "shellacking."
The night is set to be a long one. The polls began closing on the East Coast at 2300 GMT, but battleground Alaska won't close until 0500 GMT Wednesday. And even then, some ballots from remote regions won't be counted until they arrive in the capital, by seaplane.
Stay tuned to see how it plays out.