| Election Date | State | Title | Outcome |
|---|---|---|---|
| Nov. 4, 2008 | Colorado | Amendment 59: Education Funding and TABOR Rebates | Failed |
| Nov. 5, 2019 | Colorado | Proposition CC: Retain revenue for education and transportation | Failed |
| Election Date | State | Title | Outcome |
|---|---|---|---|
| Nov. 4, 2008 | Colorado | Amendment 58: Severance Taxes on the Oil and Natural Gas Industry | Failed |
| Nov. 4, 2008 | Colorado | Amendment 46: Discrimination and Preferential Treatment by the State | Failed |
| Nov. 1, 2011 | Colorado | Proposition 103: Temporary Tax Increase for Public Education | Failed |