Gun control advocates have little hope of making progress in DC after Election Day. Even if Hillary Clinton beats Donald Trump, the Democrats will not likely take control of the House, and may not even win the Senate, leading to a hopelessly divided capital. House Republicans have already vowed to investigate a president Clinton for various alleged misdeeds—meanwhile, the rest of America will have the pleasure of at least another two years of gridlock.

But that's not the case on the state level. On Tuesday, important gun safety measures will be on the ballot in four states: California, Maine, Nevada, and Washington. This shows how the fight over gun control has shifted since Congress failed to pass gun legislation in response to 2012's Newtown massacre. According to USA Today, seven states have passed or expanded background checks since that school shooting.

"Newtown changed the gun debate," Adam Winkler, a professor of Second Amendment law at UCLA, told me. "Newtown, and the failure to pass federal gun control laws, encouraged gun control advocates to focus on the states, and state-level reforms."

"We have this sense that it's totally stalled, when, in truth—while nothing is really functioning in Washington at all—we are seeing a very vibrant gun reform movement at the state level," he added. "And frankly, the NRA is active there, and in some states, it's looking to make the gun laws more loose. But in a lot of states, we're seeing gun control advocates really assert their power for the first time in many, many years."

Winkler has a point: Although the NRA has spent money against all four of these measures—the group opposes pretty much any measure that would limit anyone's access to guns—the polls show that a majority of voters in these states support them. Here's what these ballot items would do:

The "Safety for All" Proposition 63, devised by Lieutenant Governor Gavin Newsom, would prohibit the possession of large-capacity ammunition magazines. The proposition would also require customers to be subject to a background check and obtain California Department of Justice authorization before buying ammo—a permit that, legally, must be checked by a dealer, who must also undergo a background check to sell ammunition. Lastly, it'd create a court process to prevent those who are prohibited from using firearms from continuing to buy them.

California already has some of the toughest gun laws in the country. Actually, Winkler says, most of what's in Prop 63 was enacted by the state legislature earlier this year, after the Orlando shooting. Restrictions on high-capacity magazines and background checks for ammunition purchases already exist in California; the proposition's new features include the background checks for ammunition dealers, and the court process for keeping guns away from felons during their probation process.

High-capacity magazine bans tend to be favored by those who back restrictions on assault weapons—critics of those policies, including Winkler, have pointed out that they don't have much of a bite. "We've had [a high-capacity magazine ban] for maybe a year and a half, in Los Angeles, two years in San Francisco, and all the reports to the police indicated that nobody was turning in high-capacity magazines," Winkler said. "They could've sold them across state lines, to other jurisdictions, but there's no evidence of that, either."

"So you have an example of a law that has large, widespread noncompliance," he continued.

Winkler noted that tough gun laws in California are undermined by lax gun laws in states nearby, but added that, generally speaking, states with stricter gun control regulations have lower crime rates and homicide rates. That said, he said he favors Prop 63's background checks for both ammunition buyers and dealers, as it helps to close a critical loophole.

"We say that it's illegal for a felon to buy a gun at a gun store, but if that felon goes and buys a gun on the black market, they can then go to a gun store and buy the ammunition," he said. "He'll be able to buy ammo from a black market, sure, but we might as well make it difficult when he doesn't. Some won't, but you make it harder for those who will."

Liberal California, naturally, is in favor of more gun control—advocates have outspent the NRA six to one, and nearly 68 percent of Californians support Prop 63, according to polls.

Both of the initiatives in Maine and Nevada have to do with background checks.

Question 3, as the ballot measures is known in Maine, would require background checks before a gun sale or a transfer between two people if they are not licensed firearm dealers. Question 1, in Nevada, is a bit less strict, requiring all transfers—except those that are temporary or between immediate family members—to go through a licensed dealer; an exchange that would include a background check. (The federal Brady Bill requires licensed firearms dealers to perform checks on unlicensed buyers—except private or online dealers are exempt from the law. This is the famous "gun show" loophole.)

Daniel Webster, a gun violence researcher and professor at John Hopkins University, has studied the impact of similar laws in Connecticut and Missouri. Those states, in addition to background checks, require a license for those making handgun purchases, as well as fingerprint identification. Connecticut also mandates safety training for gun permit holders.

"What we found is incredibly consistent," Webster told me. "Having the policy [of requiring background checks in more situations] was protective of basically having fewer homicides, fewer suicides, and even fewer law enforcement officers shot in the line of duty." He admits, though, that "there is not much research that extend background check requirements to private transactions without a licensing provision—not solid research."

"We had published research showing that having such policies in place is associated with fewer guns being diverted for criminal use shortly after sale," he continued.

The latest polls show the measures have 54 percent approval in Nevada, and 52 percent in Maine.

The measure up for a vote in Washington State, known as Initiative 1491, would allow immediate family members or law enforcement officials to notify and urge a court to issue what's known as an "extreme risk protection order," which would disarm an individual who they strongly believe to be dangerous to themselves or those around them. A similar civil court procedure already exists in cases that involve domestic violence, or restraining orders. Not coincidentally, the "extreme risk protection order" is also known as a "gun violence restraining order."

This measure is the most popular of the four, with a July poll finding that 73 percent of Washingtonians supporting it.

According to Webster, data on this specific type of law is scarce, but the research done on states that connect firearm prohibitions to domestic violence or restraining order cases show a "significant reduction" in a partner homicide. "So that supports the general idea," he said. "I think the logic is sound, the procedures are something that most would consider to be fair, and there's reason to believe that this could be impactful."

Webster added that the most common crisis situation where an "extreme risk protection order" would be necessary is with suicide risks, so, specifically in Washington, an initiative like this could have an impact. "Suicides with guns outnumber homicides with guns almost two to one," he explained. "This could be a mechanism in states where—this is the case in Washington—the ratio of suicide to homicide is more stark. Such measures could help them reduce suicide rates."

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