HARRISBURG — A report issued Tuesday says Pennsylvania should adopt changes to make its elections more secure — encouraging the replacement of older voting machines, enhanced security of voter rolls and better contingency planning for cyberattacks and other technological challenges.

The Blue Ribbon Commission on Pennsylvania’s Election Security report urges the General Assembly to do more to help counties pay for machines that produce a voter-marked paper record.

“The lack of a paper trail prevents Pennsylvania’s counties from having the usual means for detecting any hacking or error, then recovering from such an event,” the commission said. “In the event of a suspected attack, without a paper record, counties would be unable to verify that voting records on machines were accurate.”

The report warns that U.S. adversaries are expected to increase efforts to influence elections during the 2020 presidential race.

About four in five Pennsylvania voters use machines that lack an auditable paper trail, although state officials have directed counties to have the paper-record voting machines in place by next year’s primary.

The total cost statewide for new machines has been estimated at $125 million, with federal support for a small portion of it.

The report warned that voter registration databases are a target for hacking, among the “threat vectors” it identified, along with tallying methods and election night reporting. Among its suggestions is to mail notices to registered voters whenever their records have been changed online.

“The architecture is complex and was not built to withstand threats from nation-states and other sophisticated attackers,” the report said. “Private election vendors play an outsize role in many Pennsylvania counties’ election efforts. For many, unfortunately, we fear that security is far from a top priority.”

It suggested plans for an attack should include backup paper supplies, training for workers and protocols for power outages and natural disasters. Among the recommendations is a potential change to the Election Code to allow elections to be suspended or postponed in the event of large cyberattacks, natural disasters or other emergencies that disrupt voting.

The Department of State, which oversees the county-based election system on a statewide level, said it has recently formed a group to study postelection audits and hopes to implement them in the coming years.

The effort to upgrade voting machines across the country became more urgent after the 2016 election, when Russia was accused of targeting state election systems. After the midterm elections in November that brought heavy turnout, there were reports in other states of equipment failing or malfunctioning.

State officials say they have seen no evidence that voter rolls or vote results have been hacked or otherwise compromised in Pennsylvania. Precinct election results are taken by hand to county offices, and official election results are also physically delivered, to the state, once the counties have certified them.

The commission noted there are still ways that someone could interfere with the accurate collection and tabulation of votes.

“There are multiple potential points of exposure during tallying and election-night reporting. The primary concern is an attack that could compromise the integrity or the availability of the tabulation of votes,” the report said.

The state has also provided training and guidance to counties on cyber practices, including pre-election testing, strategies to combat phishing and advice on managing passwords and permissions.

A group of five state senators plans to announce election reform measures Tuesday that would include a constitutional amendment to allow greatly expanded use of absentee ballots.

They are also unveiling proposals to give counties the option of using “voting centers” as alternatives to precincts and of adopting curbside voting for disabled people.

They also say the state could adopt new standards for how many votes it takes to win as a write-in and consolidate smaller voting precincts.