The vast majority of Americans oppose funding cutbacks or other radical changes to Medicare and Medicaid, and most are worried about the programs' financial stability, according to a new poll.

Nearly 90 percent of those surveyed called for either no change to spending or more spending on Medicare, according to a Friday poll from Kaiser Family Foundation. When it comes to Medicaid, 84 percent felt the same way.

Most people in the poll said they're worried that the programs aren't financially stable. For example, about 54 percent are worried Medicare won't be able to provide the same level of care for future beneficiaries.

As expected, Democrats favored increased government spending on Medicare (54 percent) and Medicaid (53 percent). Among Republicans, 61 percent said they wanted to keep spending flat for Medicare, and 54 percent called for flat spending on Medicaid, the poll said.

Americans also weighed in on potential changes to the entitlement programs. There was strong support (80 percent) for allowing the federal government to negotiate with drug companies for lower prices.

But other changes that would increase costs for users didn't fare as well. Only about 26 percent of those surveyed prefer a fixed premium support system for Medicare. Under such a system, the government contributes a certain amount to seniors who would apply that contribution toward the purchase of traditional Medicare or a private plan.

Currently, Medicare gives all seniors the same defined set of benefits, Kaiser said.

The premium support system is one of the ideas in prior Republican budgets drafted by Rep. Paul Ryan, R-Wis.

Kaiser surveyed more than 1,800 adults living in the United States. The survey was conducted to assess the public perception of Medicare and Medicaid as the federal programs celebrate their 50th anniversary later this month.