Colorado Newsline reported that proponents of a ballot measure establishing a graduated income tax declared victory on Thursday as a narrow lead held steady with an estimated 90 percent of the statewide vote counted. Amendment 87 repeals the state constitution's flat-tax requirement and institutes a tiered system for higher earners, with the Associated Press calling the race Friday morning when the measure had more than 51 percent of the vote.
The measure hikes corporate and individual income tax rates to 7.4 percent for income above $500,000 and 8.4 percent for income above $1 million. State legislative staff estimated the measure will raise $2 billion in additional revenue by the 2027-28 fiscal year. Alongside Proposition NN, which raises the annual revenue growth cap under the Taxpayer's Bill of Rights, Amendment 87 marks a major change to state tax policy since TABOR passed in 1992.
Opponents led by Advance Colorado challenged the measure and backed a countermeasure, Proposition 136, which aimed to cap income tax rates at 4.4 percent. The Associated Press also called the race for Proposition 136 on Friday morning after it fell behind by more than 5 percentage points.
