An effort to put a non-binding referendum on the ballot recommending that Illinois lawmakers ban gay marriage with a constitutional amendment has come up short.

Jim Finnegan, president of the conservative group Illinois Defense of Marriage Initiative, told the Chicago Sun-Times that he expects about 100,000 of the 500,000 signatures needed to put the issue on the November ballot to be collected by the end of the month.

In February, less than a year after the state approved a measure that recognizes gay and lesbian couples with civil unions, three openly gay lawmakers introduced a gay marriage bill.

Finnegan said his group's effort to block gay marriage from being legalized in Illinois sends a strong message.

“Those people that brought this bill up, they'll bring it again and again,” Finnegan told the paper. “This gives us a strong indication of who will be heard on this.”

State Rep. Greg Harris, a Democrat and the primary sponsor of the proposed gay marriage law, said that he did not believe state lawmakers would debate the measure this year.

“I never say never,” Harris said. “[But] I don't think there will be a push before the end of this session.”