Updated Nov. 5, 7:23 a.m. | Republicans swept the Senate races Tuesday night, and come January, they will control the chamber for the first time in eight years.
Democratic incumbents fell right and left, even in seats that they had originally been favored to win. President Barack Obama's poor approval rating — 42 percent in the last nationwide Gallup poll — dragged down candidates across the country in the face of a Republican wave.
Senate Minority Leader Mitch McConnell, R-Ky., who cruised to victory in his own re-election, is set to become the next majority leader , with a gain of at least seven seats — one more than the GOP needed.
As results were still pouring in, National Republican Senatorial Committee Chairman Jerry Moran credited the GOP's recruiting, encouraging and training its candidates.
"They are why we have the ability to deliver a majority, this evening, of Republicans to the United States Senate," the Kansas Republican said. "This is a great moment for us as Republicans — the ability to win and carry states that are purple and often lean blue," he added. With results still outstanding in the Virginia Senate race, Moran said the committee had invested more than $600,000 in the race, as well as an influx of money in the state over the weekend.
As expected, Republicans picked up Senate seats in West Virginia, Montana and South Dakota — three open seats where Democrats retired in the face of Republican leaning electorates. But the party went well beyond the easy pickings, eclipsing its 6-seat pickup in the 2010 GOP wave and with a few states still outstanding.
In Arkansas, GOP Rep. Tom Cotton was quickly declared the winner almost as soon as polls closed at 8:30 p.m. eastern time, ousting two-term Democratic Sen. Mark Pryor by an astonishing 18 points.
Republicans scored a big victory in Colorado, with Rep. Cory Gardner toppling Democratic Sen. Mark Udall by 5 points. Colorado Democrats had been predicting a tight race similar to 2010, when the nail-biter was called for now-Democratic Senatorial Campaign Committee Chairman Michael Bennet in the wee hours of the following morning.
The sixth seat came in North Carolina, where Democratic Sen. Kay Hagan fell to Republican Thom Tillis. It was a major blow to Democrats, as Hagan had held a narrow lead in most public polling until the final few weeks of the race.
When the Iowa Senate race was called for Republican Joni Ernst shortly before midnight, it was icing on the cake. Her win over Democratic Rep. Bruce Braley flipped the seat currently held retiring by Sen. Tom Harkin, giving the GOP a seventh seat.
Two surprisingly big wins for Republicans came in their two most vulnerable seats, Kansas and Georgia, where fumbling Republican candidates had endangered the GOP'S chances . Sen. Pat Roberts, R-Kan., defeated independent Greg Orman by 11 points, and Republican David Perdue cleared 50 percent of the vote in Georgia, avoiding a runoff with Democrat Michelle Nunn. The final margin was 53 percent to 45 percent.
In Virginia, where Sen. Mark Warner had appeared to be cruising to victory, the Democrat remained in a dead heat by Wednesday morning with 99 percent of precincts reporting. Republican Ed Gillespie trailed by less than 4,000 votes, prompting murmurs of a possible recount.
A rare bright spot for Democrats was New Hampshire, where Democratic Sen. Jeanne Shaheen held off a strong challenge by former Sen. Scott P. Brown, R-Mass. As expected, Democratic incumbents were re-elected in Oregon and Minnesota. Democrats held the open seat in Michigan, electing Rep. Gary Peters to replace retiring Sen. Carl Levin.
Results were still outstanding in Alaska, where Democratic Sen. Mark Begich faced Republican Dan Sullivan, but the outcome of that race will not affect the majority. The Begich campaign had said the senator — who was down 4 points when all the precincts had been reported but the race still not called — would make a statement once the outstanding villages were counted and the number of outstanding absentee and questioned ballots was clear.
No matter the Alaska result, the political world now turns its efforts to Louisiana, where Democratic Sen. Mary L. Landrieu is headed to a runoff with GOP Rep. Bill Cassidy. With 98 percent of precincts reporting, Landrieu finally pulled out to a small lead, but was still 8 points shy of clearing the 50 percent threshold to avoid a runoff.
Republican National Committee Chairman Reince Priebus said the RNC has more than 300 people heading to the Pelican State.
"We've already got the hotel contract," he said. "We're just trying to figure out what to do about Thanksgiving with 300 staffers or more staying on the ground in Louisiana."
Related: House Republicans Win Largest Majority in Decades Final Rankings: The 10 Most Vulnerable Senators Roll Call Event With Top Senate Campaign Aides Thursday Roll Call Results Map: Results and District Profiles for Every Seat Get breaking news alerts and more from Roll Call in your inbox or on your iPhone.