Dozens of super PACs, dark-money and special interest groups have pumped more than $50 million into Chicago-area congressional races in the run-up to the March 17 primary — and voters are understandably confused.

Major dollars have also flowed into statehouse races as a host of super PACs look to boost their preferred candidates and slam the ones that don’t serve their interests. They often come with unassuming names that do not reflect their true purpose.

Federal law doesn’t require these political action committees to reveal all of their contributors until after the primary, but the Sun-Times is keeping track of who’s behind these groups. Here’s an A-Z glossary of the groups that are trying to influence your vote, with financial figures reported as of Thursday morning by the Federal Election Commission.