With a stroke of his pen, the Republican governor designated Aug. 4 as Obama Day — a holiday to honor the 44th president's accomplishments.
Obama began his political career as an Illinois state senator before being elected to the U.S. Senate and finally to president of the United States.
But Illinois residents won't get a day off work to celebrate Obama's legacy — state offices, schools and other services will remain open.
An effort to make Obama Day a legal holiday failed, with Rauner saying he was concerned about the economic impact on the state at time when lawmakers were struggling to pay a $15 billion backlog of bills.
Many fans of the former president took to social media using the hashtag #ObamaDay to wish Obama a happy birthday, and to share their favorite memories of him. He adopted Chicago as his hometown after marrying South Side native Michelle Robinson.