People arrived at 4:30 am for Wednesday's rally which continues until 6:30 pm. The Supreme Court ruling stated the federal government must recognize same-sex marriage if the state allows it. It's part of the Defense of Marriage Act which has been law since President Clinton signed it in 1996.
Illinois bans same-sex marriage, but a lot of couples in this crowd are married. They just did it in other states like Iowa. The ruling means those couples will be eligible for federal benefits.