The California Health Care Foundation, an independent nonprofit group that studies health issues, estimates that two-thirds of all residents in the district get help from Medi-Cal. Valadao represents a majority Latino district that includes most of Kings County and slices of Tulare and Kern counties.

Some in the GOP, including the president, oppose slashing Medicaid. But with cuts to Social Security and Medicare already ruled out, some argue that cuts to Medicaid may be necessary, given the spending cuts and tax cuts in the budget proposal passed by the House last week.

The House Republican drive to significantly reduce federal spending on medical care has placed the party on a collision course with the health needs of its own constituents.