Just over 800,000 Massachusetts voters had cast their ballots in the state’s first-ever early voting period as of Thursday afternoon, officials said.

“It was our first time with it and we didn’t know how people would react,” said Brian McNiff, spokesman for the secretary of the commonwealth, William F. Galvin. “It’s looking like it was pretty popular.”

The voting period started Oct. 24 and will end Friday, McNiff said. The early votes are being sealed and will be counted with other ballots Nov. 8 — Election Day — in the voters’ precincts.