Republicans won control of the U.S. Senate in Tuesday’s midterm elections, ousting several Democratic lawmakers from their seats and sending a stinging rebuke to President Barack Obama.

The GOP needed a net gain of six seats to win back control of the Senate from Democrats. As of early Wednesday, Republicans had won at least seven seats controlled by Democrats and were on track to win more.

Republicans were victorious in West Virginia, Arkansas, South Dakota, Colorado, Montana, Iowa and North Carolina. All seats had been held by Democrats.

Republicans held on to Georgia and Kansas, two states Democrats had hoped to pick-off. New Hampshire Sen. Jeanne Shaheen barely survived a challenge from Republican Scott Brown.

Meanwhile, votes are still being counted in Alaska, where Republican Dan Sullivan is challenging Democratic incumbent Sen. Mark Begich. The race hasn’t officially been called yet, but with 100 percent reporting, Sullivan is ahead of Begich 48 percent to 45 percent. That would give Republicans eight pick-ups.

In Virginia, Republican Ed Gillespie has not yet conceded, though early returns show him trailing Democratic incumbent Sen. Mark Warner by less than one point.

In Louisiana, no candidate reached the required 50 percent threshold. Democrat Mary Landrieu and Republican Bill Cassidy will face each other in a Dec. 6 run-off.

If Republicans win in Louisiana, where the Republican is leading in polls, they will take over nine Democratic seats.

While Republicans picked up several open seats previously held by Democrats, the GOP ousted at least three incumbents: In Arkansas, GOP Rep. Tom Cotton defeated incumbent Democratic Sen. Mark Pryor. In Colorado, GOP Rep. Cory Gardner beat incumbent Democratic Sen. Mark Udall. In North Carolina, Republican Thom Tillis bested incumbent Sen. Kay Hagan.

“Tonight’s results are a clear rebuke of ObamaCare and the government overreach that have come to define the Obama-Reid agenda, and a class of senators who chose to rubber stamp bad policy rather than fight for the people they represent,” said Tim Phillips of Americans for Prosperity, the conservative group that pummeled these vulnerable Democrats on the airwaves over the last year.

Mitch McConnell — the Kentucky Republican poised to become senate majority leader — defeated Democratic challenger Alison Lundergan Grimes, who benefited from millions in campaign dollars from liberal donors who wanted to see McConnell gone.

“So tomorrow, the papers will say I won this race,” McConnell said in his victory speech in Louisville. “But the truth is, tonight we begin another one, one that’s far more important than mine. And that’s the race to turn this country around, to restore hope and confidence and optimism to this commonwealth and across this nation of ours.”

Nevada Sen. Harry Reid, the Democratic leader who will now be in the minority, released a statement late Tuesday. “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.”

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