Illinois' first day of legalized marijuana sales resulted in more than 77,000 transactions, adding up to about $3.2 million, the Illinois Department of Financial and Professional Regulation said Thursday, per NBC's Chicago affiliate.

The big picture: According Chicago's mayor, the city alone is expected to take in nearly $3.5 million in pot tax revenue this year. That figure represents four months worth of revenue because tax collections do not start until September under state law. Illinois is the 11th state in the U.S. to legalize recreational cannabis, with more planning to put the issue on the ballot in 2020.

Go deeper: Illinois governor pardons 11,000 pot convictions ahead of Jan. 1 legalization