Published: Nov 05, 2013 5:30 PM EST

SPRINGFIELD, Ill. (AP) - A historic vote Tuesday in the Illinois House positioned that state to become the largest in the heartland to legalize gay marriage, following months of arduous lobbying efforts by both sides in President Barack Obama's home state.
    
Lawmakers voted 61-54 to send the measure back to the Senate to change the bill's effective date, just a technical change since the chamber already approved the measure in February. The measure will then head to Gov. Pat Quinn, who has pledged to sign it into the law.
    
Fourteen states plus Washington D.C., allow same-sex marriage. Most recently, New Jersey, Minnesota and Rhode Island have allowed it.
    
The road to the vote was long with stalled attempts earlier this year, something that frustrated activists in the state where Democrats lead the House, Senate and governor's office. Chicago Democratic Rep. Greg Harris, who is the sponsor of the bill, decided not to bring the bill for a vote in May because he said he simply didn't have the support.
    
Then the U.S. Supreme Court ruled to strike down a provision of the federal Defense of Marriage Act, something he said resonated with lawmakers. Backers also launched a furious campaign, hiring a lobbyist from the state's largest union, the former head of the Illinois Republican Party and field organizers spanning the state.
    
"To treat all our citizens equally in the eyes of the law we must change this," Harris said on the floor. "Families have been kept apart."
    
Polls show support for gay marriage has surged since 1996, when Gallup found that 27 percent of Americans backed it. Now Gallup finds the majority support giving gay and lesbian couples the right to marry.
    
Opponents of the legislation - which included some of the most powerful religious leaders in the state - have said marriage should remain between a man and a woman. A group of Chicago areas pastors vowed to line up primary challengers against some Chicago area lawmakers who voted yes.
    
"This issue is not just about two adults and their emotional relational and financial commitment to another," said Rep. Tom Morrison, a Palatine Republican. "Redefining marriage has far reaching implications in our society."
    
The measure cleared the Senate on Valentine's Day with the support of 33 Democrats and a single Republican. Backers had expressed confidence that the bill would be approved by the House in mid-March. But it took the supporters months to secure enough yes votes to win the House's approval.
    
In September, Minneapolis Mayor R.T. Rybak even went to Chicago to encourage gay couples to hold their nuptials in his city if they were tired of waiting for Illinois lawmakers to act.
    
Although Illinois once appeared poised to become the first Midwestern state to approve gay marriage in the Legislature, Minnesota did it sooner and started holding its first same-sex weddings over the summer. Iowa allows gay marriages too because of a court ruling, not a legislative vote.
    
The issue caused internal conflict among Illinois Republicans as the party works to balance efforts to appeal more to younger voters, minorities and women with the more socially conservative positions of some party members.
    
For months, the leaders of several black mega-churches lobbied the districts of black House members with an aggressive robocall campaign against gay marriage, placing an uncomfortable spotlight on the mostly Democratic black caucus. Many remained undecided until the vote neared.
    
Illinois approved civil unions in 2011.
    
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The bill is SB10
    
Online: http://www.ilga.gov

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