Today is the last day Massachusetts residents may register to vote or change party enrollment for the state election on Nov. 5.

Mail-in registration must also be post-marked by today.

Theresa Neighbor, executive director of the Cambridge Election Commission expects as many as 500 residents to register at the Cambridge Election Commission and the City Clerk’s Office.

Neighbor also said that many more people will register through the mail tomorrow and almost 2000 residents have registered over the past two weeks.

According to Neighbor, 32 percent of Cambridge residents turned out to vote in the primary—including 50 percent of active voters.

She also predicted the Cambridge turnout for the general election to be 65-70 percent—a figure up from recent elections but part of a long-term downward trend in voter participation in the city.

Both the offices of the Cambridge Election Commission and the City Clerk are open tomorrow between the hours of 8:30 a.m. and 8 p.m.

The Cambridge Election Commission is located at 51 Inman St. and the City Clerk’s Office is at City Hall, located at 795 Mass. Ave.

Mail-in registration forms can be obtained from public libraries and post offices.

—Christopher M. Loomis