A bit of background in a recent article in Americas Quarterly:
In the early 1990s, a calculation of national health accounts by the Fundación Mexicana para la Salud revealed that more than half of total Mexican health care expenditure was individual, out-of-pocket payments. Families and individuals were paying from their own incomes or savings for health care procedures, including emergency care. In other words, half of the population lacked health insurance.
It has also paid electoral dividends. According to a recent scholarly treatise of the 2006 campaign, by Alberto Diaz-Cayeros et al, the effects, and as such popularity, of Seguro Popular was one of the major factors why many poor voters went for PAN rather than the PRD in that year's presidential election.The realization that households—the poor, in particular—had been paying catastrophic, out-of-pocket sums changed public perceptions and provoked public discussion of the need to expand public health coverage. Policymakers suddenly began to look at how financial issues affected the provision of health care and levels of poverty among Mexican households.
First launched by President Vicente Fox, Seguro Popular may thus remain as one of the major social achievements of the two PAN administrations.