The main benefit of partial Medicaid expansion is to the budgets of states that opt to pursue it, because they’re effectively shunting the cost of covering the population earning between 100% and 138% of the poverty line to the federal government, which pays for the premium subsidies. But they’re still paying more to cover the population earning 100% or less than they would if they fully expanded Medicaid, since the federal match for Medicaid patients would be lower.

Source: Los Angeles Times February 13, 2019 18:11 UTC