CHICAGO (CBS) — A new poll estimates that more than four in 10 Illinois voters now support full marriage rights for gay and lesbian couples.

In the poll by the Paul Simon Public Policy Institute at Southern Illinois University, 44 percent of respondents said they believe gay and lesbian couples “should be allowed to legally marry.”

When the same institute asked that question in 2010, only 34 percent backed gay marriage.

The latest poll found 32 percent of respondents prefer civil unions for gay couples – which were legalized in Illinois last year – while 20 percent believe “there should be no legal recognition.” Opposition to any legal recognition for same sex couples was nearly 27 percent in 2010.

The poll of registered voters was conducted Sept. 4-10 by telephone – both land lines and cell phones – and has a sampling margin of error of plus or minus 3 percentage points.

Illinois State Rep. Greg Harris (D-Chicago), who is one of three openly gay Illinois lawmakers and who led the efforts to legalize civil unions, called the poll results “monumental.”

“It’s just striking how fast public opinion is changing,” he said.

Harris attributed the change to more public discussion of the issue — for example, an endorsement from President Barack Obama — and people seeing more gay friends, relatives and neighbors living ordinary lives. Harris said people look around and say, “Gosh, those families want what my family has. What’s wrong with that?”

He said that suggests the increased support didn’t come just from people who have been on the fence, but from residents who used to oppose gay marriage outright.

Back in May, Lambda Legal and the American Civil Liberties Union filed separate lawsuits on behalf of 25 gay and lesbian couples, claiming that the failure by the Cook County Clerk to issue marriage licenses to same-sex couples violates the Illinois.

The lawsuits claim that the failure by the Cook County Clerk to issue marriage licenses to same-sex couples violates the Illinois Constitution. Currently, the State of Illinois still bans same-sex marriage by statute, but the state constitution does not address the issue.

Cook County State’s Attorney Anita Alvarez and Illinois Attorney General Lisa Madigan have both refused to defend the state in the lawsuit, saying they agree the ban on same-sex marriage violates the constitution.

In their place, two downstate county clerks – Kerry Hirtzel of Effingham County and Christie Web of Tazewell County – have been approved to defend the lawsuit.

Cook County Circuit Court Judge Sophia Hall will decide later this year whether to allow three other parties to help defend the state against the lawsuit. Two suburban churches – Arlington Heights-based Church of Christian Liberty and Bensenville-based Grace Gospel Fellowship – are seeking to intervene, as is the Illinois Family Institute, an advocacy group that opposes gay marriage.

The Catholic Conference of Illinois also plans to more aggressively argue against gay marriage, said its executive director, Robert Gilligan. Brochures with questions and answers about the subject will go out to parishes around the state, he said, and pastors will receive talking points to help them discuss gay marriage more effectively.

This past Sunday, Francis Cardinal George said same-sex marriage will be detrimental to society, because the institution marriage between a man and woman “comes to us from God,” and not from the church or government.

“There must surely be ways in our civil society, where we can honor friendships, where we can respect other people, without destroying the nature of marriage. It is very important, for your whole lives, give witness to what marriage truly means. And while civil laws might change – if they do – then society will be the worse for it,” the cardinal said at a mass Sunday.

In May, Quinn said he was ready to work toward legalizing gay marriage, shortly after President Barack Obama said he favors same-sex marriages.

(TM and © Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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