WASHINGTON — BILLIONS of dollars are being spent in the run-up to this November’s midterm elections. The Supreme Court has struck down limits on campaign spending by corporations and unions, as well as overall caps on individual donations to candidates for federal office. More and more money is also being spent through ostensibly independent “super PACs” and nonprofit entities.

Even as cash gushes through the system, though, we still have a key underpinning of our campaign finance law: the principle that the public has a right to know who finances campaigns, and how candidates, parties and other political committees are using those funds. If the Federal Election Commission, the agency charged with receiving and reviewing the reports and making the information available, falls down on the job, this principle is undermined.

On May 21, about a month after reports for the first quarter of this year were filed, the research and technology teams here at the Center for Responsive Politics did a routine download of F.E.C. data, as we’ve done hundreds of times in our 30-year history. We use the information to populate a database that allows anyone to track giving by individual donors, their employers and their economic interests and to examine the links among campaign money, lobbying activity and the personal finances of politicians and key officials.

Ascertaining that contributions are characterized correctly — Did the funds come from individuals? Did they flow through another organization? Are the donors and recipients identified correctly? — has been a basic responsibility of the F.E.C. almost since its inception, along with tasks like making sure the data reflect amended filings and avoid duplication of records. This processing isn’t particularly high-tech, but it has to be done right, and quickly.