Hundreds of people gather outside the US Supreme Court building in Washington, DC on June 26, 2013 in anticipation of the ruling on California's Proposition 8, the controversial ballot initiative that defines marriage as between a man and a woman. AFP PHOTO / MLADEN ANTONOVMLADEN ANTONOV/AFP/Getty Images Hundreds of people gather outside the U.S. Supreme Court in Washington, D.C., on June 26, 2013, in anticipation of the ruling on same-sex marriage. (Mladen Antonov/AFP/Getty Images)

Illinois is set to become the 15th state and largest in the heartland to allow same-sex couples to marry. State senators approved technical changes Tuesday to a measure legalizing gay weddings, shortly after a historic favorable vote in the state House. The bill now goes to Gov. Pat Quinn, who has said he’ll sign it into law.

Quinn said the House "put our state on the right side of history" with its vote, adding "Illinois is a place that embraces all people and today, we are an example for the nation."

The state will start allowing same-sex marriages next summer.

In a statement released by the White House, President Obama had high praise for the Illinois General Assembly, where he once served.

"As President, I have always believed that gay and lesbian Americans should be treated fairly and equally under the law," Obama said. "Over time, I also came to believe that same-sex couples should be able to get married like anyone else. So tonight, Michelle and I are overjoyed for all the committed couples in Illinois whose love will now be as legal as ours – and for their friends and family who have long wanted nothing more than to see their loved ones treated fairly and equally under the law."

However, Brian Brown, president of the National Organization of Marriage, said in a statement, "The losers will be the people of Illinois who will see that redefining marriage will unleash a torrent of harassment toward those who believe that marriage is the union of one man and one woman."

He added the law lacked sufficient religious liberty protections. “Once the law goes into effect in June of next year, we will see individuals, businesses and religious groups sued, fined, brought up on charges of discrimination and punished simply for holding true to the traditional view of marriage.”

The House adopted the bill  by a vote of 61 to 54 Tuesday.

Hawaii is likely to be the next state to legalize same-sex marriage; its state Senate passed such a bill Oct. 30, and the Hawaii state House is expected to vote on the measure in a matter of days.

The group Freedom to Marry — part of the coalition that lobbied for gay marriage in Illinois  — took the opportunity to send out a fundraising appeal for its "Win More States Fund" on Tuesday night.

The group's national campaign director Marc Solomon wrote in an e-mail that while the vote marked a turning point in the state, "our work continues. In 35 states, same-sex couples are denied the freedom to marry and Freedom to Marry is implementing a bold and ambitious strategy to win nationwide."

"Today the Land of Lincoln rededicated itself to the proposition that all are created equal,” said Human Rights Campaign President Chad Griffin in a statement.  “Thanks to principled impatience from state leaders in Springfield, the overwhelming momentum toward nationwide marriage equality continues to intensify.”