Several states have proposed single-payer health care bills over the last year, suggesting that Americans are losing patience with the struggling individual market, and losing confidence in the federal government’s ability to fix it.

These types of proposals are not particularly unusual—at least ten states have released single-payer health care bills over the last few decades. But the conversation around universal health care seems to be changing, and it seems increasingly plausible that one of these proposals could attempt to serve as a model for the country.

Below, we’ll outline the most recent single-payer proposals, but let’s first take a look at what single-payer health care really means.

Universal health care, or single-payer?

Terms like universal health care, single-payer health care and Medicare-for-all are often used interchangeably, but they aren’t exactly the same thing,

Universal health care is the broadest term, and it refers to any health policy where every citizen has access to coverage and care.

Single-payer or Medicare-for-all are ways to accomplish universal health care. Under this type of system, there is—you guessed it—a single source of payment for medical services, typically the government.

Here is a rundown of some recent state proposals, and where they stand.

Healthy California California’s state assembly shelved a single-payer bill last week, but the Senate-passed legislation would have created a “Medicare-for-all” plan. It was expected to cost $400 billion per year, covered by a 15 percent increase on payroll tax and existing state and federal funding spent on Medicaid and Medicare.

New York Health Act This single-payer bill passed the state assembly in May—as it has three times before. The New York Health Act has never made it out of its next hurdle—the state Senate. This proposal is expected to cost $200 billion per year, funded by a payroll tax increase and taxes on capital gains.

ColoradoCare

This bill failed in a public referendum last November. It was expected to cost $25 billion per year, and would have been funded by a 10 percent increase to payroll taxes.

Nevada Care Plan

The Nevada universal health care plan is a little different. It would have allowed all Nevadans to purchase Medicaid insurance, which is usually only available to low-income consumers or those with disabilities, but Governor Brian Sandoval vetoed the bill last week. The governor did say the proposed bill “may play a critical role” in future policy.

The Nevada Care Plan was a version of what’s called the “public option,” which is a state-run insurance plan. For consumers with incomes too high to qualify for regular Medicaid, there would be premiums, but those eligible for Affordable Care Act subsidies could use their credits to purchase Medicaid. The bill’s sponsors had not decided whether it would have other cost-sharing functions, like deductibles or coinsurance, before it was vetoed.

The lack of detail was a major issue for the Nevada Care Plan—the bill was just four pages long.

But it did gain some support in the state. The Nevada Hospital Association changed its position from opposing the bill to neutral, which is notable—providers typically prefer private insurance to Medicaid, because private insurance reimburses at a higher rate.

Growing support for single-payer, but challenges remain

Nationally, Medicaid coverage has one of the highest satisfaction rates among consumers, which Michael Sprinkle, the sponsor of Nevada’s Medicaid-for-all bill, cited as inspiration. Gallup polls have consistently found that consumers with government health plans, like Medicare or Medicaid, have higher satisfaction rates that those with private insurance, who are more affected by cost-shifting trends.

Supporters of single-payer health care often point to those satisfaction rates as proof that a government-run health plan would be preferable to the current system. This, along with Senator Bernie Sanders’ presidential campaign, which called for Medicare-for-all, seem to be contributing to growing single-payer support.

That said, plenty of challenges remain. Funding is always an issue, and rising taxes is a turnoff to many consumers. Other consumers disagree with the premise that a government-run system would be an improvement on a privately-based one.

But despite the challenges, it could take just one success story. If one state is able to develop a working universal health care plan, consumers across the country could warm up to the idea.