A sign in Little Rock notes the need for photo ID, following the passage of a law in Arkansas requiring it.Danny Johnston / AP

There is a variety of origin stories for why Missouri is known as “the Show-Me State.” But if Republicans in the state legislature get their way, it could take on new meaning for voters headed to the polls—as in, “Show me your photo ID.”

The state senate, which is overwhelmingly Republican, is considering a double-barreled proposal. One part is a joint resolution that would place a ballot measure before voters to create a constitutional amendment requiring voters to show photo identification to vote. The other part governs how the requirement would be enforced if approved; in particular, it would require the legislature to fund programs to help get voters who don’t have some form of ID a card. If there’s no money, the requirement wouldn’t go into effect. The House already passed both halves in January. Senate Republicans brought the issue up Wednesday, but Democrats filibustered until 2 a.m., and the issue was temporarily set aside.

Democrats have repeatedly obstructed attempts to pass the measures. Republicans are expected to bring it up again before the end of the session on May 13, and may use procedural measures to try to end the Democratic filibuster. If they succeed, Governor Jay Nixon, a Democrat, could veto the the bill, but his veto would likely be overridden. He can’t veto the joint resolution.

Missouri is one of several states to bring up tighter voting-related laws over the last few years. The bill under consideration is one of the stricter laws to come up since North Carolina passed a passel of rules to tighten voting regulations in 2013, including shortening early voting, eliminating same-day registration, and a photo-ID requirement. That law, in turn, has been described as the nation’s strictest since the Supreme Court’s 2013 decision in Shelby County v. Holder eliminated a requirement that jurisdictions with a history of discrimination pre-clear new voting laws with the Department of Justice, which had effectively blocked most stricter laws. The North Carolina law is subject to a court challenge. A federal judge on Monday ruled against plaintiffs challenging the law, but the decision has already been appealed, and the Fourth Circuit said Thursday it would expedite the case. Many experts expect the Supreme Court to have the final say.

The arguments in Missouri are familiar from North Carolina and elsewhere: Republicans argue that voter-ID laws are essential to preserve the sanctity of elections, lest fraudulent votes be cast. Besides, they say, state-issued photo ID is required for a range of normal activities, like driving a car. Is it really so much to ask people to produce one before they vote?

Democrats and other advocates respond that such laws are simply tools of voter suppression. They point out that there are next to no documented cases of voter fraud, and describe bills like this as a solution in search of a problem. They also note that driving a car, unlike voting, is not a fundamental right, and point to the fact that studies have shown that such laws are most likely to affect poor, young, and minority voters. (For example, Missouri’s changes would exclude photo ID from state universities.) It’s no coincidence, they say, that those are blocs that overwhelmingly vote Democratic.

In some states, Republican lawmakers have slipped up and said just that. “Now we have photo ID, and I think photo ID is going to make a little bit of a difference as well,” U.S. Representative Glenn Grothman of Wisconsin said earlier this month. In 2012, the Republican leader of the Pennsylvania state house said voter ID was “gonna allow Governor Romney to win the state of Pennsylvania.” (Instead, a judge blocked the law and Obama won the state.)

“Missouri is one of those swing-ish states where you’ve got Republican control and the thinking is that this could make a difference, like North Carolina,” said Rick Hasen, a professor of law of the University of California, Irvine, and election-law expert. Barack Obama narrowly lost the state in 2008, and while it might not be on the map in 2016, there is a Senate race, too.

Missouri voters already have to show some form of ID to vote, but the requirement is liberal—accepted documents include an expired license, an out-of-state license, a student ID, utility bills, paychecks, and more.

“This is a piece of discrimination,” state Representative Joe Adams, a black Democrat from St. Louis, said in January. “It is Jim Crow in its worst form. And I would be embarrassed if I voted for this piece of legislation. I would be embarrassed to look at my children.”

In 2014, Secretary of State Jason Kander, a Democrat, released a report on the effect such a law would have and estimated that 220,000 voters could be disenfranchised under the law, though it’s not entirely clear how Kander calculated that number:

Among the hundreds of thousands of eligible Missouri voters that could be kept from voting by HB 1073 are students with current school-issued photo ID’s, senior citizens who no longer drive, Missourians who rely on public transportation, and women who have changed their last names due to marriage or divorce.

State Senator Will Kraus, one of the leading backers of the bill—and a Republican candidate to succeed Kander, who is running for U.S. Senate—has pointed to a few cases. “There’s over 16 people in the state of Missouri who have been convicted of some type of voter fraud. That shows people in the state of Missouri are trying to cheat elections,” Kraus said in January. But as PolitiFact noted, the cases that Kraus pointed to are all cases of fraud in registration—not cases of voter impersonation, which is ostensibly what voter-ID laws combat. Kander’s 2014 report stated, “There has not been a single case of voter impersonation fraud reported to the Secretary of State’s office.”

In Missouri, not only are the arguments familiar—the fight is, too. Republicans have been trying unsuccessfully to tighten the state’s laws for a decade now. A 2006 attempt was passed and signed into law, but the state supreme court struck it down as an unconstitutional infringement on the right to vote, in part because it forced citizens to assume the cost of obtaining ID.

In 2011, Governor Nixon vetoed another attempt. There were not enough votes to override him. The following year, state Republicans tried again, this time using a constitutional amendment to sidestep the supreme court ruling. But a judge ruled that attempt unconstitutional, too, and it was excluded from the ballot.

Voter-ID laws tend to do well on the ballot. One notable exception is in Minnesota, where Democrats mobilized and blocked a constitutional amendment in 2012. Doing that might be harder in Missouri, a redder state.

As conservative-leaning states work to impose stricter voting laws, liberal ones are working to make it easier to vote. On Thursday, Vermont Governor Peter Shumlin signed a law that automatically registers citizens to vote—when they sign up for a driver’s license or state ID, Missouri Republicans might archly note. Vermont is the latest in a string of states to adopt automatic voter registration. It’s a sign of how polarized the U.S. has become that in a nation founded on the premise of democracy that red and blue states increasingly are so divided even on that fundamental right.