Illinois is on the path to officially recognizing same-sex marriages this week.

After its failure to approve an identical Senate bill in May, the Illinois House passed the measure 61-54 on Nov. 5. Gov. Pat Quinn, a Democrat, pledged last week to sign the bill into law.

The marriage equality legislation makes Illinois the 15th state in the nation to permit same-sex marriage and the second state in the Midwest, behind Iowa, to allow the unions. It’s a decision that has the potential to spark a similar push in Missouri, said Jeffrey Mittman, American Civil Liberties Union of Missouri director.

“It’s time for Missouri to join Illinois and Iowa in treating all families equally,” Mittman said in a press release last week. “It is our goal to do whatever is necessary to make sure that day comes soon for Missourians. The federal government has stated that it is clearly unconstitutional to refuse to recognize the marriages of some families.”

While Missouri constitutionally banned same-sex marriage in 2004, the roadblocks to legalization are now far fewer in number than expected, Mittman said.

“We know that every year, more and more Americans say they want equality for their lesbian and gay family and friends,” Mittman said.

A.J. Bockelman, director of the Missouri LGBT rights group PROMO, was more cautious in his aims to legalize same-sex marriage west of the Mississippi.

As of now, PROMO has all legalization options — legislation, a ballot initiative or a court ruling on same-sex marriage — on the table, Bockelman said.

“None of those are necessarily a guaranteed process,” Bockelman said. “They all take significant resources, and it takes a lot of public education around the issue. That said, though … none of them are simple, direct or easy.”

PROMO in recent months has hosted joint town hall meetings with the ACLU and attempted to educate Missourians on same-sex couples’ rights, Bockelman said.

The organization is still evaluating the most effective way to bring marriage equality to next year’s election season.

Thanks to the U.S. Supreme Court’s U.S. v. Windsor decision, Missouri residents still benefit from the Illinois ruling. Missourians can cross the border for marriage licenses and still maintain federal recognition of same-sex marriage in Missouri.

“While it will have a limited benefit in Missouri, there is still a benefit in having a recognized marriage from one of the 15 states that recognize (same-sex) marriage,” Bockelman said.

Illinois native and senior Dan Stribling, a staffer at the LGBTQ Resource Center, was excited at the prospect of his home state’s turn toward marriage equality, Stribling said.

“It was a long process,” Stribling said. “It was good to finally get it done, especially since Illinois has been a reliably blue state for a long time.”

However, of the same legislation’s potential in Missouri, Stribling was wary. Though advocates like Bockelman and Mittman regularly cite a majority opinion among Missourians in support of same-sex marriage, public officials could still bring the issue to a standstill, Stribling said.

“Our state legislators and our state senate overwhelmingly oppose marriage equality,” Stribling said.