The two campaign committees behind the ballot question — Coloradans for Prosperity and Great Education Colorado — spent a combined $4.5 million on the failed effort, according to final campaign finance reports filed late last week.
Colorado voters 54% to 46% to reject Prop. CC, which would have ended the tax revenue caps in the Taxpayer’s Bill of Rights.
The measure’s opponents spent at least $1.8 million, most of it from dark money organizations that didn’t disclose the source of the campaign cash.
All told, the five issue committees spent more than $10 million in the 2019 election on the two statewide ballot initiatives. About $3.8 million of that spending backed the successful Proposition DD measure to legalize sports gambling.