As if anyone watching needed confirmation of the very negative tone the 2012 election has taken, a new report from the Wesleyan Media Project notes that 70 percent of TV spots aired so far for the presidential race have been negative.

First, a caveat: since an ad being positive or negative is a subjective matter, researchers simply cut through the problem and designated any spot mentioning an opponent as negative. So of course there are a few ads here and there in that 70 percent that merely mention another candidate without attacking him or her. But what really matters in this analysis is how 2012 compares to 2008. The election four years ago looks quaint compared to today: only 9.1 percent were negative at this point four years ago.

Why such a drastic spike in negativity? As the story's always gone in 2012, it's because of Super PACs. "Whereas in 2008, candidate-sponsored ads made up 96.6 percent of total 'airings,' as of April 22, 2012, that percentage had dropped to 35.8 percent," The Huffington Post's Sam Stein writes. Super PACs, which are legally unable to "coordinate" with the more cautious heads of the candidate's campaigns, can say audacious things on a candidate's behalf. And if a Super PACs goes too far, a candidate can simply ask it to pull back -- which is still not considered coordinating for some reason.