The Attorney General’s Office and a lawyer for the plaintiffs said a longer extension would reduce the chances of another website crash and additional court proceedings.

“The thinking is we’ll provide ample time so it will spread the burden on the network over the weekend and into Monday,” said John A. Freedman, an attorney with law firm Arnold & Porter LLP, which helped bring the case.

“If the system crashes again, we’ll have to deal with it,” Hilton said.

Virginia Department of Elections officials said the website problems were caused by an unprecedented traffic surge and online voting promotions by Facebook and Google. An unknown number of people who tried to register online ahead of Monday’s deadline were met by a “File not found” error message.

In a statement, McAuliffe, who has focused extensively this year on expanding voting rights for felons, said the state will “fully comply” with the order by reopening voter registration online, in person and by mail.