Top election officials from two US states warned a congressional panel that confidence in elections has been eroded by ideological efforts to discredit the system that have spawned unrelenting threats against election workers.
"This is a vicious cycle that must be mitigated for the good of our country," New Mexico Secretary of State Maggie Toulouse Oliver, a Democrat, told the House of Representatives Administration Committee, which oversees federal elections.
Ms Toulouse Oliver was one of six state election officials who appeared before the committee for a hearing about public confidence in the 5 November election.
She warned that elections have been colored in the public mind by "conspiracies, misinformation and, frankly, outright lies" that have led to threats, violence and frivolous public information requests.
Democratic Michigan Secretary of State Jocelyn Benson said the spread of false information is driving threats that have unleashed "an omnipresent feeling of anxiety" among election administrators.
"People have come to my home. They have threatened me or my staff and many of the hundreds of clerks and local election officials in our state," Ms Benson said.
"Unsubstantiated allegations and rhetoric without evidence makes our elections less secure, because they erode the public's confidence," she said.
Neither Ms Toulouse Oliver nor Ms Benson identified those they said were seeking to discredit US elections.
In recent weeks, Republican Donald Trump has stepped up his false claims that the 2020 election was stolen from him and maintains without evidence that this year's contest could be swayed by votes from people who have crossed the US-Mexico border illegally.
Congressional Republicans this week are trying to force Democrats to accept legislation sought by Mr Trump that would require proof of citizenship from those registering to vote in federal elections.
Republican committee Chairman Bryan Steil said the bill dubbed the Safeguard American Voter Eligibility Act is needed to prevent noncitizens from registering to vote while obtaining driver's licenses.
"Because noncitizens can receive drivers' licenses in every state, they inevitably also receive voter registration form seven though they cannot vote in federal elections," Mr Steil said.
"As a result, we have seen states take steps to remove those noncitizens from their voter rolls."
Democracy advocates and Democrats view the measure as a Republican attempt to cast doubt on the November election.
"Our elections are secure," said Representative Joe Morelle, the panel's top Democrat. "Americans will not succumb to the torrent of mis- and disinformation."
Ms Toulouse Oliver cited claims of noncitizen voting as an example of the misinformation that diminishes voter confidence.
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"Noncitizen voting simply does not happen in any systematic way in New Mexico or in the nation more broadly," she said. "However, voters believe noncitizen voting does occur and this impacts our overall confidence in elections."
Voting by noncitizens is a felony offense and has been shown by independent studies to occur only rarely.
Ohio Secretary of State Frank LaRose, a Republican, told the panel that voters in his state are concerned about noncitizen voting as a result of record flows of migrants into the country.
"It's rare, but we keep it rare by enforcing the law," said LaRose, who said his office has removed nearly 600 noncitizens from state voter rolls. "This problem has only been compounded by the lack of border security under the current administration."
Ohio has about 8 million registered voters in total, according to state records.
West Virginia Secretary of State Mac Warner, a Republican, criticized Mr Biden for using a 2023 executive order to direct federal agencies to help people register to vote and called for the repeal of the federal law that allows driver's license applicants to register to vote.
