Abstract Direct democracy is often used to shape state-level health policy, and while prior research has studied determinants of success for ballot measures generally, examination of healthcare-related measures (HRM) remains limited. This study addressed four questions: (1) are HRM more likely to pass than non-healthcare-related measures (NHRM); (2) do HRM engage voters more than NHRM; (3) do HRM draw more oppositional campaign spending than NHRM; and (4) among HRM, what characteristics predict success? We identified 96 HRM in 34 states from 2010-2024 and 352 NHRM that appeared alongside them on the same ballot (n = 448). Using regression analyses to examine campaign outcomes, ballot completion, and spending, we controlled for initiative- and election-level covariates. Sensitivity analyses adjusted for “moral issues” (i.e., measures pertaining to abortion and euthanasia) and supermajority passage requirements. Findings indicate that HRM drew greater voter engagement and were significantly more likely to pass than NHRM. Furthermore, increased oppositional spending was associated with lower odds of success for all measures. Results indicate that interest groups and voters view HRM pertaining to “morality” differently and among HRM, oppositional spending is the strongest predictor of success. Additional research is needed on voter preparedness when it comes to healthcare policy on the ballot.
McMurtry et al. (2026) studied this question.