- States that expanded Medicaid had greater political participation (measured in terms of voter registration and turnout). This is consistent with the theory that social policy programs increase political engagement. https://www.cambridge.org/core/journals/american-political-science-review/article/politics-of-policy-the-initial-mass-political-effects-of-medicaid-expansion-in-the-states/246aa0f10b44efd62a7b27c661730823 1995 comments science