Paper ballots are making a comeback thanks to Russian hacking fears.

SAN FRANCISCO – Once about as newsworthy as water meters, the voting machines and computers used to record and tally the nation's ballots are suddenly a hot button issue due to mounting evidence Russia tried to interfere in the 2016 U.S. presidential elections.

According to the FBI, as many as 39 states had their election systems scanned or targeted by Russia. There's no evidence of votes changed. But given the stakes, some state agencies that run elections are trying to curb any further interference prior to mid-term elections in November.

Their tool of choice: Ensuring systems can't be hacked, and if they are, making those breaches immediately obvious. To do this, some are taking the unusual move of rewinding the technological dial, debating measures that would add paper ballots — similar to how many Americans voted before electronic voting started to become widespread in the 1980s.

A week ago Virginia announced it would no longer use touch-screen-only voting machines after a hack-a-thon in Las Vegas showed how easily they could be breached.

States with electronic-only voting machines want to add a paper back-up that would mandate, for every electronic ballot cast, creation of a paper version that could be counted, and presumably, not easily altered.

Rhode Island is set to vote on a measureTuesday that would require an audit of voters' paper ballots after each election.

Georgia is fighting a suit by voters that, among other claims, alleges the state needs to switch to a paper-ballots-based voting system because it now uses touch-screen voting machines that do not meet the requirements of state law due to their age and vulnerability to hacking.

The U.S. voting machine industry is dominated by three privately-held companies, Election Systems & Software in Omaha, Neb., Dominion Voting Systems in Toronto and HartInterCivic in Austin, Texas.A wholesale refitting of the nation's voting machine infrastructure would represent a sizable sales opportunity for them. But there's little money in the system to make that happen, say experts.

Too often voting officials lack the resources necessary to protect and upgrade election infrastructures, said Lawrence Norden, at the Brennan Center for Justice at the New York University School of Law and author of a report in June called Securing Elections from Foreign Interference.

“The federal government says it’s up to the states to fund it, the states often put it down to the counties and the counties say they have no money. So we need some shared responsibility for funding elections and making sure they’re free and fair," he said.

Virginia dumps touch-screen-only voting machines

Even so, some states are moving to overhaul their voting apparatus to be more secure. Last week, Virginia’s Board of Elections voted to replace touch-screen-only voting machines used in 22 localities in the state to those that have paper back-ups.

They did this after hackers at DefCon, a computer security conference, demonstrated in July that they could easily break into them.

Touch-screen voting machines are considered insecure because they don’t produce a paper copy of the vote and therefore can’t be rigorously audited. Voting integrity activists aren't advocating returning to a totally paper-based voting system, but instead requiring that voting machines produce a paper record that can be used to check the reported electronic totals.

“The step we took today to decertify paperless voting systems is necessary to ensure the integrity of Virginia’s elections,” said James Alcorn, chair of the State Board of Elections, in a statement.

Dean Logan, head of the California Association of Clerks and Election Officials and also the registrar-recorder for Los Angeles County, said some of his workers attended DefCon. Hackers' ability to break into voting machines was a fresh reminder that agencies needed to make the process more secure.

“My staff came back with pretty eye-popping stories about when people have physical access to the voting equipment, that they can do things and they can do them pretty quickly,” he said