Senate Republican Leader Mitch McConnell defeated Tea Party challenger Matt Bevin in the Kentucky primary contest.

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The Associated Press called the race for McConnell over his Tea Party-backed challenger, Louisville businessman Matt Bevin, within minutes after the polls closed at 7pm ET.

As an experienced campaigner with a huge war chest, McConnell was able to fend off Bevin’s strong, early challenges, closing the race in the final months with a double-digit lead that he rode to victory.

The race for the Kentucky Senate seat has become one of the most high-profile in the 2014 cycle, with McConnell having to defend himself against two well-funded attacks  -- the Tea Party claim that he is not conservative enough and now Democratic challenger Allison Grimes’ charge that his conservative leadership has denied Kentucky residents jobs and health care.

At present, every poll has McConnell’s race against Grimes, Kentucky’s secretary of state, as a dead heat with Election Day just six months away.

Grimes also easily won her Tuesday primary.

Her race with McConnell also is expected to be the most expensive congressional race this election cycle, as Republicans try to win a net six seats to take control of the upper chamber. If that happened, McConnell would replace Nevada's Democratic Sen. Harry Reid as the Senate majority leader.

Both candidates already have spent millions yet still have cash remaining -- roughly $10 million for McConnell and $5 million for Grimes. Much of the money is coming from interests outside  the state -- including Hollywood money eager to knock off the top Senate Republican and McConnell supporters trying to stop what they in part consider overspending by the Obama administration, including ObamaCare.

"She's able to raise money because she is running against me," McConnell recently said of Grimes. "I'm able to raise money because I am me."

They have raised a combined $19 million in the two years leading up to their primaries.

McConnell and his allies are already running television ads comparing Grimes to Obama, whose disapproval rating in Kentucky is at least 60 percent.

This week, two of the support groups  -- Kentuckians for Strong Leadership and the Kentucky Opportunity Coalition -- put down a combined $5.2 million for general election ad time.

Conservatives are unhappy about McConnell's compromises with Democrats to raise the debt ceiling, pass the Wall Street bailouts and other fiscal issues.

"I think he'll have a very tough time bringing them back," Grimes campaign manager Jonathan Hurst said earlier this week. "We will welcome those who vote against Sen. McConnell and his own party on Tuesday to join our campaign."

Josh Holmes, a McConnell campaign adviser, said the primary gives McConnell's camp an advantage by forcing it to get the campaign running early.

"Our campaign has been up and running at full speed for six months," Holmes said. "We are able to get through the primary election with an operation that we feel confident about that we are able to test and we're able to carry into the fall that has some success already under its belt."

The Associated Press contributed to this report.

A panel discussed McConnell's win and Super Tuesday on tonight's "On The Record." Watch it above.

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