With more than $770 million in campaign and Super Pac spending for Obama this year, the forces supporting the president have spent about $5.33 per registered voter when you calculate using the total number or registered voters in the last campaign, which was just over 146.3 million.
Romney's team, similarly, has spent about $4.81 per voter. Combined, that's $10.14 per registered voter.
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Compare that to how much it cost to reach registered voters in 1980: The $528 million spent by Reagan and Carter campaigns plus their parties reached fewer voters — 105 million registered voters. That made total spending over $5 per registered voter.
Twenty years later, George W. Bush and Al Gore and their party committees combined spent $899 million to reach that year's nearly 130 million registered voters. That's just under $7 per registered voter.
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By our math, the cost to reach each voter in America has gone up consistently over the past three decades. There's lesson in that for the campaigns and the fundraisers who push for ever more cash each year: that flood of money is causing political inflation. And that makes the constant reach for new fundraising records a self-fulfilling prophesy.
—By CNBC's Eamon Javers and Jessi Joseph