CFI:

Independent expenditures (IEs) spending for congressional primaries went up once again. This unsurprising conclusion was based on a Campaign Finance Institute (CFI) analysis of data supplied by the Federal Election Commission for all federal primaries from 2006 through the last ones of September 2018. Perhaps more striking than the bottom line totals, however, were some of the stories that show up in the subtotals.

As is well known, IEs went up sharply after two court decisions in 2010 (Citizen United v. Federal Election Commission and SpeechNow v FEC), nearly doubling every election between 2008 and 2014. (See Table 1) The rate of growth seemed to ease a bit in 2016, as independent spenders turned toward the presidential election. But 2018 showed growth once again – not at the explosive rates of 2010-2014, but at a level that is still well worth noticing (30% above 2014 and 41% above 2016).

The pattern has not been uniform. More IE money was drawn toward Senate than House primaries in 2012, 2014 and 2016 when few political experts thought the House majority was likely to change. But with control clearly at stake in 2018, IEs in House primaries almost pulled even with those in the Senate.