| Election Date | State | Title | Outcome |
|---|---|---|---|
| Nov. 4, 2008 | Colorado | Amendment 58: Severance Taxes on the Oil and Natural Gas Industry | Failed |
| Nov. 3, 2020 | Colorado | Proposition 114: Reintroduction and Management of Gray Wolves | Passed |
| Nov. 5, 2024 | Colorado | Proposition 127: Prohibit Hunting of Mountain Lion, Bobcat, and Lynx | Failed |
| Nov. 5, 2024 | Colorado | Proposition 129: Establish Qualifications and Registration for Veterinary Professional Associate | Passed |