CONNECT WITH:

By Rachael Marcus, The Center for Public Integrity 

Mitt Romney

Since Labor Day, the once-unofficial start of the election season, 70 percent of outside spending on the presidential race made possible by the Citizens United Supreme Court decision has benefited Mitt Romney, according to a Center for Public Integrity analysis.

More than $106 million of the $117 million spent on the Obama-Romney matchup since Sept. 3 has been on negative ads, with President Barack Obama absorbing more than $80 million in attacks, according to the analysis of Federal Election Commission data.