Prior to Obamacare, most states limited Medicaid to the very poor, blind, disabled, and pregnant women and children. Today, states can extend the program to adults earning up to about $17,000 a year. (Image: Shutterstock)

For years, elected leaders in conservative states have resisted expanding Medicaid, the government health program for low-income Americans. Now voters in four of those states will decide the question directly.

Ballot initiatives in Idaho, Utah, Nebraska, and Montana will test whether there's a disconnect between politicians and voters over a program that insures 1 in 5 Americans at an annual cost of more than half a trillion dollars to federal and state governments. Advocates behind the measures in states carried by President Donald Trump in 2016 aim to distance Medicaid expansion from the law that makes it possible: the Affordable Care Act.

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“This isn't Obamacare—this is Medicaid,” said Ray Ward, a Republican state lawmaker and physician from outside Salt Lake City. Ward supports widening eligibility for Medicaid in Utah, and says many of his constituents do too. While solidly Republican, his district is “not an angry sort of Tea Party district,” he said.