Ad tracking firm Kantar Media Intelligence/CMAG has put together a chart comparing spending between the Koch brothers' Americans for Prosperity and two major Democratic outside groups, the Senate Majority PAC and the House Majority PAC. It's not even close:
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Of course, this doesn't offer a complete picture of all third-party spending this cycle. But even if you added everything together, Republicans would still have a big edge. The question is whether Democrats will be able to achieve something closer to parity as Election Day draws nearer—and whether the effects of this early assault can be reversed, or if the damage is permanent.