Governor Pat Quinn of Illinois signs same-sex marriage into law Wednesday, making President Obama's home state the 16th to allow such unions. (Reuters)

Illinois Gov. Pat Quinn (D) signed a bill legalizing same-sex marriage Wednesday, making his state the 16th to allow gays and lesbians to marry.

Quinn signed the bill at a ceremony at the University of Chicago-Illinois. After signing the bill, Quinn stood and raised it over his head with one arm as the sizeable crowd applauded.

The governor then tweeted:

 

 

The state legislature passed the legislation two weeks ago after some delays. The state will begin allowing gay marriages starting in the summer.

Hawaii last week became the 15th state to legalize gay marriage.