TALLAHASSEE, Fla. -- Backers of a proposal to change the constitution to ban gay marriage fell short Wednesday as the deadline passed for garnering enough support to get the amendment on this year's ballot.

The other group that appeared to have a shot to continue its effort to get on the ballot as Wednesday's 5 p.m. deadline approached was Florida4Marriage.org. The group, backed by the Republican party, wants the Florida constitution to define marriage as the union between one man and one woman. Florida law already states the same.

Organizers mounted a last-day push to get petitions turned in, but fell short turning in only about 455,000 signatures of the 611,009 needed, said John Stemberger the leader of the petition effort.

"It was an amazingly strong showing considering the resources we had," Stemberger said. "If it takes another two years it's worth the wait."

Gov. Jeb Bush said earlier this week that if the measure didn't succeed, he may talk to lawmakers about whether the state law that already defines marriage needs strengthening, or constitutional protection. He noted that there's no current challenge to the law, but said it would be hard to respond after the fact if someone did successfully challenge it.

"Hopefully it just won't succeed because it's the wrong thing," said Pastor Paul Anway, who performs gay union ceremonies - not legal marriages - at a Christian church in Tallahassee. "When we see people, groups and organizations using a religious standpoint to oppose this, it feels very discriminatory, it feels like they're trying to create a group of second-class citizens."