CHICAGO (CBS) – A vote by state lawmakers on a bill that would legalize civil unions for same-sex couples could come as soon as Monday, reports say.

Illinois State Rep. Greg Harris (D-Chicago) is sponsoring HB 2234. The legislation would grant new spousal rights to same-sex partners in a civil union, putting them on par legally with heterosexual married couples when it comes to surrogate decision-making for medical treatment, survivorship, adoptions and accident and health insurance, for example.

But the legislation does not recognize same-sex marriages.

Illinois House Speaker Michael Madigan said last week that the odds are favorable that the House will approve the bill.

“I think there’s a good chance it’ll pass,” Madigan said, giving the initiative a significant boost.

A vote could come as soon as Monday, according to Gay Chicago Magazine.

Backers, including Gov. Pat Quinn, have set a goal of getting the legislation to the governor’s desk by year’s end despite opposition from socially conservative and religious organizations.

Advocates for civil unions have been working throughout the week to convince legislators to vote for the bill.

Rick Garcia, public policy director of the gay rights group Equality Illinois, said he and several other advocates went to Springfield to lobby for the bill. He told Gay Chicago Magazine that people are “very excited about the possibility” that it might pass.

Volunteers also packed the Equality Illinois offices at 3318 N. Halsted St., calling members of the group and encouraging them to contact their legislators, Gay Chicago Magazine reported.

Garcia told the magazine he is also trying to get Republican support for the measure. Harris said people should urge family and friends to call their legislators, particularly if they live in the suburbs or downstate, the magazine reported.

“Our enemies who think we should have no rights whatsoever are out there calling,” Harris told Gay Chicago Magazine.

The group LGBT Change and the Civil Rights agenda has also launched an outreach campaign. They have set up phone banks on the city’s North, South and West sides, as well as Evanston and Oak Park, and plan to urge 20,000 voters across the state to contact their state representatives in favor of the bill.

“Groups from around the country are helping with phone-banking, including California, Iowa, Michigan, Minnesota, New York, Washington D.C., Washington State, and Wisconsin,” a news release from the group said.

But the bill also faces stiff opposition from some groups, including the Francis Cardinal George and the Catholic Conference of Illinois. Francis Cardinal George said in a news release that “everybody has a right to marry, but no one has the right to change the nature of marriage.”

Even though the civil unions bill would not legalize same-sex marriage, George said in a news release that “the public understanding of marriage will be negatively affected by passage of a bill that ignores the natural fact that sexual complementarity is at the core of marriage.”

The Catholic Conference went on to express concern that the bill will infringe on “religious liberty,” and might force faith-based institutions to place adoptive children with same-sex couples, force Catholic parishes or social service agencies to provide services to couples in civil unions, or refuse to protect small employers that will not extend family benefits to employees with same-sex partners.

Garcia said the bill will be called when there are 60 votes in the state Senate and 30 in the state House.

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