For much of the early 1960s, House Ways and Means chairman Wilbur Mills represented the “One-Man Veto” on Medicare before eventually offering his reluctant support to the measure in 1964 and 1965. Ironically, this longtime opponent would be the one to suggest an expansion in the scope of the bill. Early proposals for Medicare only offered to cover hospital costs; Mills would call for physician costs to be covered, as well. The aim of this thesis is to show how Mills’s expansion of Medicare benefits in 1965 caused health care costs to skyrocket in the late 1960s, causing the fiscally conservative Mills to co-sponsor legislation for a single-payer national health insurance program along with Senator Edward Kennedy almost a decade later.