A bill that passed the New Hampshire Senate along party lines and is now winding its way through the state House would impose additional voter registration requirements and harsher penalties for those who violate them. Voting rights advocates say the measure would make it much more difficult for low-income people and students to register to vote, and possibly violate the National Voter Registration Act.

Republicans in the key northeastern swing state have been attempting to pass voter registration restrictions for several years—some of which were vetoed by past Democratic governors or struck down by courts. But with a Republican-controlled House and Senate and a newly installed Republican governor, the measure appears likely to become law this year.

Under the bill, voters who register within 30 days of an election would have to fill out an additional multi-page form and present documents proving that they intend to reside permanently in the state—such as as a utility bill, lease, or proof of college enrollment. Voters would no longer be able, as they do now, to sign an affidavit swearing they are a permanent state resident.

Voting rights advocates who oppose the policy say they are most concerned about those who take advantage of the state’s same-day registration policy, who under the new bill would have to sign an affidavit and mail a proof of residence to the county clerk within 10 days of the election. Local municipal offices, which get no additional funding under the bill, would have to verify the documents. If a voter cannot access the proper documents or forgets to send them in, they can be charged with voter fraud and fined up to $5,000 dollars.

“Who is that going to impact? Low-income folks, people who are more transient, victims of domestic violence who have had to move, and college students,” said Gilles Bissonnette, the legal director of the American Civil Liberties Union of New Hampshire. “Talk about having a deterrent effect on the right to vote. This statute would charge them with ‘wrongful voting’ even if they live in New Hampshire, call it home, but just don’t have the right documents.”

This week the town of Durham, home to the University of New Hampshire, passed a resolution condemning the bill, warning it would “inhibit legally established citizens from voting” and would add “unnecessary and overly onerous” steps to the state’s voter registration process.

The ACLU and some local officials say the measure would particularly burden thousands of college students in the state, who change addresses every year.

“Students [in dorms] don’t have formal leases and don’t receive utility bills, said Bissonnette. “And the time they move the most falls squarely within the September primary that we hold every two years.”

Some Republican lawmakers, meanwhile, have been explicit about their intent to target students, arguing that out-of-state college students should not be allowed to vote at all, even if they live in the state for four years or more.

“If you are only going to school in Keene or Durham, and that’s not really where you live, and you’re staying on campus or you’re renting an apartment or you’re part of a frat house, then you don’t really live there. You’re going to school there,” said former Republican Senate Majority Leader Bob Clegg, testifying this week in support of the bill.

Other ex-officials have been blunter still. Former Republican House Speaker Bill O’Brien famously advocated in 2011 for restricting ballot access for students because they have a tendency toward “voting as a liberal.”

“They don’t have life experience, and they just vote their feelings,” he said.

New Hampshire’s voting laws have come under increased scrutiny following evidence-free claims from President Donald Trump and members of his administration that thousands of residents from neighboring states were bused in to vote illegally in 2016, tipping the state in Hillary Clinton’s favor. Some Republican state legislators have echoed these conspiracy theories.

Yet New Hampshire’s longtime Democratic Secretary of State Bill Gardner has shot down these allegations, saying there is no proof of widespread voter fraud in the Granite State. Republican Governor Chris Sununu and former Republican Attorney General Tom Rath have publicly agreed.

“Is there clear evidence of voter fraud here? I don’t know of any,” Sununu told New Hampshire Public Radio.

Yet the governor and the secretary of state are backing the bill to require proof of domicile from those registering to vote, citing the need to address the “public perception” of widespread voter fraud.

“It really begs the question of why this is necessary in the first place,” Bissonnette told TPM. “We should be legislating based on actual problems, not perception.”

Bissonnette further warned that New Hampshire could violate the National Voter Registration Act by implementing the new policy. Because the state offers same-day registration, it currently has an exemption from the federal requirement for all DMVs and government offices to offer voter registration forms. The ACLU testified before a state House committee on Tuesday warning that “this bill, if enacted, would compromise New Hampshire’s NVRA exemption.”

Kansas offers a cautionary tale. The state worked for years to add a proof of citizenship requirement to its voter registration forms—which would have disenfranchised thousands of eligible residents—only to see the measure struck down in court for violating the NVRA.

There is no sign, however, that New Hampshire will back away from such policies. Earlier this year, Republicans introduced a host of other voting restrictions in the state legislature, including bills to eliminate same-day registration, step up enforcement of voting laws, and narrowing the number of documents accepted under the state’s voter ID law. Most of the bills died in committee, but the proof of residency provision appears to be headed to the governor’s desk.