Conservative groups are pouring money into Georgia's 6th District runoff to reinforce Karen Handel's bid for Congress. Jon Ossoff is readying a massive counterpunch.

The Democrat’s campaign has reserved more than $5.2 million in airtime for cable, TV and radio spots through the June 20 runoff. And that’s likely just a taste of what’s to come.

The former congressional aide reported raising more than $8.3 million through the end of March, but this ad buy suggests he’s added millions more to that fundraising haul in the weeks since the last filing deadline.

Handel’s campaign, meanwhile, has taken in at least $1.75 million since she landed the No. 2 spot in the matchup – a total that includes about $750,000 from Donald Trump’s visit on Friday. The Republican hasn’t aired a TV ad since the election, but she’s had ample backup.

The Congressional Leadership Fund, a super PAC with ties to Paul Ryan, said it was pouring in another $3.5 million into the contest and has already reserved nearly $3 million in ad time.

The National Republican Congressional Committee has paid for $3.65 million in airtime, while the U.S. Chamber of Commerce launched a nearly $1 million ad blitz on Monday.

The race to represent the district, which spans from east Cobb to north DeKalb, has become the premier political contest of the year and is a test of Donald Trump's popularity. It's also shaping up to be the most expensive House race ever, with both parties pouring money and resources into the contest.

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