UPDATE 2:13 PM: The Illinois House has voted in favor of marriage equality. Governor Quinn has previously announced his intention to sign the bill into law. I'm hearing that gay marriage will become legal in Illinois on June 1st, 2014.

Original Post: BuzzFeed says:

The Illinois House will take a final vote on marriage equality legislation Tuesday, a leading advocate tells BuzzFeed. Previously, sources had said a vote would not take place until Wednesday at the earliest.
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If passed in the House, the bill will be sent back to the Senate for a vote. The Senate already approved the previous version of the bill earlier this year.

Good luck, Illinois.