To start, what a Super PAC is not: "A popular video game for smartphones."
No shame though if that was your initial thought. A statistically significant number of people, when asked a question like the one in the headline and given four potential answers, chose the option quoted above.
Nor is "Super PAC" the nickname for a "Congressional committee on the budget deficit" (9 percent of respondents). Many would argue that Super PACs are far more efficient than any body formed in the halls of the House or Senate.
Only 40 percent of Americans, according to last week's Washington Post/Pew Research poll, correctly identified Super PAC as groups "able to accept unlimited political donations."
For the other half (and then some), here's a brief primer:
Before Super PACs became "super," they were just PACs, or Political Action Committees. The groups could support a candidate or a cause, but were heavily regulated under the terms of campaign finance law. Individuals were allowed to give $2,500 -- no more -- and corporations and unions were strictly forbidden from making donations.
In 2010, that all changed. Two court cases decided in the space of two months re-wrote the book on campaign spending and ushered in the era of the Super PAC. First, there was the Supreme Court ruling now referred to simply as "Citizens United."
The story begins six years earlier, when Conservative nonprofit group Citizens United filed a complaint with the Federal Election Committee (FEC), the body charged with refereeing campaign finance disputes, saying television ads for Michael Moore's "Fahrenheit 9/11" were effectively -- and illegally, because Election Day was so close -- advocating against President George W. Bush's re-election. The FEC rejected the claim, so Citizens United decided to start a production company of its own. Three years later, its "Hillary: The Movie," an unsympathetic documentary about then-candidate Clinton, was completed and ready to air on DirecTV. But the FEC, backed by a lower court ruling, blocked the group from running ads promoting the film.
By the spring of 2009, the case had made its way to the Supreme Court. After some legal gymnastics, the question before the justices was broadened and on January 21, 2010, the decision came in. The Court struck down all caps on the amount of money a person could give to a PAC.
More controversially, the ruling also declared that corporations and unions could also make unlimited donations.
Super PACs are barred from coordinating activities with any candidate or campaign, but the dividing line is murky. The two most closely dedicated to supporting the Obama and Romney campaigns, respectively, are run by former aides to the president and his Republican challenger.