The voter registration deadline technically arrives on Tuesday for Illinois residents who want to cast a ballot in the March 20th primary. But it’s kind of a soft deadline.

To vote on March 20th at their local polling place, voters who aren’t already registered must do so by the end of the day.

“This is the official end of registration in all the traditional ways,” Cook Cook County Clerk David Orr said.

Orr explains those “traditional ways” include mailing in a registration form, or by going to the secretary of state’s office or to a local village clerk.

But Illinois residents who miss the Tuesday deadline are not out of luck. Starting Wednesday, they can take advantage  of what’s called “grace period registration and voting.”

“It still can be done, but it’s a lot more difficult than if you register before the deadline on Tuesday,” Orr said.

Orr’s office, which handles voting for suburban parts of Cook County, has six grace period locations. Chicago’s election board has just one: its headquarters downtown.

HOW TO REGISTER: Suburban Cook County, Chicago, DuPage County, Lake County, Will County, McHenry County, Kane County and Kendall County