Now that super PACs' spending in the 2012 election has just crossed the $100 million spending mark—more than twice the amount spent in independent campaign expenditures by all outside groups at this point in the 2008 election–Sunlight decided to reflect on what else voters might have gotten for all that money.

With $100 million, you could:

• Pay the annual tuition for 2,207 students at most expensive undergraduate education in the country—Columbia University;
• Snap up 632 median-priced single-family homes in metropolitan areas from the country's housing market;
• Fill the tank of the most gas-guzzling SUV—a Chevrolet Suburban—more than 700,000 times, or
• Send more than 5,000 infants through full-time child care in Washington, D.C.

Instead, the outside political spending — more than $120 million of it if you include all independent expenditures by party committees, traditional PACs and other outside groups such as nonprofits — went in considerable part to run negative campaigns. According to a Sunlight analysis, 56 percent of the outside money spent thus far has gone to oppose candidates. And a report in today's New York Times suggests that the negative tone may be about to get much worse, with one major super PAC funder considering racially-tinged ads against President Obama.

Independent expenditures are communications to voters made in support of or against the election of a candidate that are not supposed to be coordinated with candidates' campaigns. Most of this money goes to TV and radio advertising.

(MORE: download all of the independent expenditures in the 2012 election)

The $105 million that super PACs have now doled out, according to Sunlight's Follow the Unlimited Money tracker, underscores the rapidly growing importance of outside groups on the campaign. The amount represents almost seven times what was spent by outside groups on independent expenditures in the 2004 election through this point, according to data from the Center for Responsive Politics. If you do not include the spending of party committees in 2004, the super PAC spending in this election exceeds the total spent on independent expenditures by outside groups in the entire 2004 election by about $35 million. 

Since the two 2010 court decisions that upended federal limits on campaign contributions, Citizens United and SpeechNow, more than 400 super PAC have been formed. Most are funded by a relatively small group of donors writing fat checks. Nearly $80 million came from just five super PACs—all of them supporting one of this year's leading GOP presidential contenders: Mitt Romney, Newt Gingrich, Rick Santorum, Ron Paul and Rick Perry. 

More than $103 million of the total super PAC spending has come from just 36 super PACs—those that have spent $100,000 or more. Of those 36 super PACs, only nine are pro-Democrat. Just seven percent of the money was spent by groups supporting Democrats — a fact that may reflect greater success raising high dollar checks from GOP donors, but also the lack of a Democratic presidential primary contest this spring.

In fact, congressional contests have been drawing more outside expenditures than the Democratic presidential campaign so far, as shown in this breakdown of this cycle's independent expenditures: 

• GOP presidential candidates: $90 million
• Barack Obama: $1.8 million
• Senate candidates: $14.3 million
• House candidates: $13.9 million

Other than the presidential race, the Senate races that have attracted the most money so far are GOP primaries in Indiana, Texas, Nebraska and Utah, all attracting over $1 million. While the Nebraska and Indiana Senate primaries are over, the Texas and Utah races have yet to be decided.

The four House races that have been the most active have all been special elections: New York's 26th and 9th districts, Oregon's 1st and Nevada's 2nd district. 

It's worth nothing that all of this independent expenditure spending doesn't include the millions of dollars that are spent on "issue ads" that criticize or back candidates but do not call for their defeat or election, and the amount of the many of the buys will never be reported to the FEC. These ads are generally conducted by 501c4 nonprofit groups that do not disclose their donors, unlike super PACs. One recent study, using data from TV ad buys, found that $30 million has been spent on general election ads by these dark money groups—the vast majority of it against President Obama.