Missouri voters have strongly approved a new law that rejects a key provision of President Barack Obama's health care overhaul.
Tuesday's vote approving the ballot measure is seen as largely symbolic because federal law generally trumps state law. But it could portend trouble for the Democratic Party in November's midterm election.
Legislatures in other states have passed similar measures. But Missouri is the first state to challenge aspects of the law in a referendum.
Missouri's law prohibits the government from requiring people to have health insurance or from penalizing them from paying for their own health care. That conflicts with a federal requirement that most people have health insurance or face penalties starting in 2014.