The return of paper ballots for all Virginia voters, a process begun a decade ago and accelerated by the threat of hacks of computerized voting machines, has kicked into high gear a month before the next state election.

Edgardo Cortés, Virginia's commissioner of elections, said last week all of the commonwealth's cities, towns and counties will use paper ballots and electronic scanners on Nov. 7, ensuring voting and tabulation are secure.

"The issue here is not whether it's hackable or not," Cortés said in an interview. "The issue is if you end up with some kind of question, you have those paper ballots you can go back to."

The danger is not theoretical.

The Department of Homeland Security last month notified Virginia and 20 other states about Russian efforts to hack their election systems in 2016.

On Wednesday, Sen. Mark R. Warner (D-Va.), vice chairman of the Senate Intelligence Committee, told reporters he was concerned Russians continue to try to interfere with U.S. balloting, especially in swing states such as Virginia.

"To make a change, even on the national level, doesn't require penetration into 50 states," Warner said. " . . . You could pick two or three states in two or three jurisdictions and alter an election."

"A state like mine, in Virginia, and in New Jersey, in 34 days, we have an election," Warner said, noting DHS has pledged to offer additional assistance to the two states with gubernatorial elections in November.

Cortés said Russians never penetrated Virginia's databases last year and only scanned some of the state's "public-facing" websites, looking for opportunities or errors.

The state reported those forays to the FBI at the time.

In July, at the DefCon hacking conference, programmers successfully invaded 30 Direct Record Electronic (DRE) touch-screen machines, including some identical to those in use in Virginia, within 90 minutes.

Virginia general election guide

The hackers then posted how they broke in and posted passwords that would allow copycats to mimic their actions.

In response, the state Board of Elections decertified the touch-screen machines in September, requiring 23 cities and counties that use them — including Falls Church and Alexandria — to acquire new voting equipment in a tight time frame.

The affected localities serve 140 of the state's 2,439 voting precincts, or about 190,000 of the state's 5 million active voters.

David Bjerke, the Falls Church registrar, said he spent about $150,000 for the new equipment. Anna Leider, Alexandria's registrar, said that city will spend about $594,000, money that had been in next year's budget.

The cost of replacing the systems is borne by local governments, and many of the communities that were using touch-screen machines are in poor, rural areas. Cortés said his office worked to arrange payments they could afford.

Paper ballots, once marked with a voter's choices, will be inserted into an electronic scanner that will record the votes. The ballot itself will be retained if it's needed for a recount.

The scanner prints out a results tape and records the totals on a secure thumb drive, which goes to the local election headquarters for the official canvass, or count, the next day.

Election officials emphasized no equipment is connected to the Internet, and even registration rosters known as poll books, typically kept on stand-alone laptops, are backed up with paper printouts.

The change to a paper-based ballot system will make Virginia's process "one of the very best" in the country, said Barbara Simons, president of the nonpartisan Verified Voting.

"In far too much of the country, people are voting on insecure machines," said Simons, who has written a book about electronic voting machines and whose work led to the cancellation of Defense Department Internet voting project. "The very idea that a local election officer without enough money or technical expertise would be able to protect these machines is absurd."

Activists concerned about the lack of a paper trail in electronic voting persuaded the General Assembly in 2007 to prohibit local registrars from replacing electronic voting machines with other electronic machines and instead return to paper balloting.

The deadline for completing that transition was supposed to be July 1, 2020.

That transition accelerated in 2015 when hundreds of WINVote machines were decertified after voters, including Gov. Terry McAuliffe (D), complained they had trouble casting ballots.

The WINVote machines, which were prone to crashing and vulnerable to cyberattacks, were dubbed "America's worst voting machines" by Wired magazine, in part because of poorly secured WiFi features used to tally votes.