WASHINGTON -- Independent groups spent over twice as much as political parties in the May special election to represent New York's 26th Congressional District, following a trend that began after the Supreme Court decided to allow groups to raise and spend unlimited sum of money in campaigns.
These groups spent $1.6 million, compared to the nearly $700,000 spent by political parties. As is usually the case, the candidates spent more than any independent or party-affiliated group, with a combined total of $7 million on the special election.
The vast majority of the outside money came from two groups: American Crossroads, a GOP group affiliated with Karl Rove, and House Majority PAC, a group run by former Democratic Congressional Campaign Committee staffers. These two combined to spend over $1 million on the special election.
The spending disparity between independent groups and the political parties began in the 2010 midterm elections after the high court opened the door to unlimited outside group fundraising and spending.
Spending by outside groups has ebbed and flowed since the passage of the McCain-Feingold campaign finance reform law in 2002 reaching its zenith in the 2010 midterm elections.
According to a study by the Campaign Finance Institute, independent spending grew by 130 percent in 2010 from 2008 levels while party spending dropped by 20 percent over the same period. The total amount spent by independent groups rose from $119 million in 2008 to $280 million in 2010.
The special election in New York's 26th District featured three candidates: Democrat Kathy Hochul, Republican Jane Corwin and Tea Party candidate Jack Davis.
The majority of spending by the outside groups came in the form of media advertising. Independent groups spent $1.1 million of the total $1.6 million on television and radio advertising. Nearly all of that money was spent on negative advertising.
Corwin was the biggest target of independent groups because both candidates and the groups supporting them primarily focused on attacking her. On the other hand, Republican independent groups split their spending attacking both the Democrat, and eventual winner, Kathy Hochul and the independent Tea Party candidate Jack Davis.
Infographic created by HuffPost's Chris Spurlock.