"After Walmart's new policy takes effect in January, many part-time workers who stand to be denied company health benefits would eventually qualify for Medicaid once the Obamacare expansion takes effect in 2014.... But if states now threatening to forgo the Medicaid expansion follow through on those plans, many Walmart employees -- along with others in low-paid, service-sector positions -- run the risk of slipping through the cracks: They are likely to work too few hours to qualify for company benefits, yet earn too much to qualify for Medicaid under their states' restrictive standards."