The final figures are in: The 2014 election was the most expensive midterm election in history, costing a grand total of $3.77 billion. But for the first time since 1990, fewer Americans donated money in this midterm election than the one before. Simply put, more money went into the system, but fewer people provided it.

On Nov. 5, the Center for Responsive Politics projected the 2014 election would be the most expensive midterm ever based on how much was spent through early October. A new analysis taking into account year-end filings confirms that projection — and finds our estimate was low by roughly $104 million.

Among the most significant findings that can now be confirmed is that there were far fewer identifiable donors in the 2014 election than in the 2010 cycle. Then, CRP counted 869,602 donors; in 2014, we have been able to identify just 773,582 — a decline of more than 96,000, or about 11 percent. (A caveat: Our figure accounts only for those who gave more than $200, since the FEC does not require donors of less than that to be itemized on campaign finance reports.)

The trend held true for candidates and political parties as well as […]