Edited Oct 16. And Oct 20

The short answer: Yes, assuming there wasn’t a hugely funded campaign prior to 2008. As of Oct 16, the Yes and No campaigns on I-1631 have raised over $38m. The two previous biggest spending campaigns (I-1183 liquor privatization in 2011 and I-522 GMO labeling in 2013) topped out in the $32.6m range.

The long answer: The Public Disclosure Commission has data going back to 2008, so that’s what I’ll focus on. (Is it possible that there was a more expensive measure earlier than 2008? Sure. But that seems fairly unlikely because of real factors like population growth, as well as more gimmicky factors like inflation.)

I found two measures in the data set with over $20m in total spending. One was Initiative 1183 (liquor privatization) in 2011, which raised $20.1m Yes and $12.4m No, grand total of $32.5m.

The other was Initiative 522 (GMO labeling) in 2013, which is complicated:

  • There were 6 funded Yes campaigns, totaling $9.9m.
  • There were two No campaigns, one from Grocery Manufacturers Association that spent $12.9m and one from “No on 522” that spent $22.456m. But the GMA campaign transferred most of its money to the No on 522 campaign: the C4 reports show transfers to the “No on 522” campaign of of $472.5k on May 8, $1.75m on Aug 22, $5m on Sept 27, $2.9m on Oct 24, $877.5k on Oct 25, for a total of exactly $11m. Most of the rest of the GMA money seems to have been spent on activities unrelated to I-522: a search for “unrelated to I-522” in the expenditures spreadsheet totals $1,671,922.32; the remaining amount that was spent on I-522 totals $11,229,499.42, of which $11m was transferred to the “No on 522” campaign. So the total spending is $11.229m plus $22.456m minus the $11m double-counting, for a total of $22.7m.
  • Grand total of $9.9m plus $22.7m equals $32.6m.

Initiative 1631 (carbon fee) in 2018 reports the following as of PDC reports available on the morning of Oct 20: the Yes campaign has raised $12.5m and the No campaign has raised $25.8m, total of $38.3m.