ST. LOUIS — A battle is shaping up next year on the Medicaid expansion of the health care act, pitting state Democrats against Republicans.

Democratic Gov. Jay Nixon embarked on a statewide tour Thursday to publicly support increasing the number of Missouri residents who can join the Medicaid rolls.

The U.S. Supreme Court ruling in June on the Patient Protection and Affordable Care Act allows states to decide whether they will accept federal funds to allow those families and individuals making up to 138 percent of the federal poverty level to receive Medicaid.