PHOENIX - The state could be blocked from enforcing its new law aimed at illegal immigrants for more than two years if opponents can gather enough signatures to refer the issue to voters.

Andrew Chavez, who officially began a referendum of the legislation on Wednesday, said he plans to take as much time as he's legally allowed to gather the 76,682 valid signatures he needs to put the issue to the ballot.

Chavez, a professional petition circulator acting on behalf of a client he would not identify, has until 90 days after lawmakers wrap up the current session to get the signatures, which means he has at least until the last week of July, leaving little time to verify the signatures before this year's ballot has to be printed.

Matthew Benson, spokesman for the Secretary of State's Office, said Wednesday that doesn't necessarily mean action on the measure will be stalled until the next election in 2012.

The office will work as fast as possible, he said, but he isn't sure they can get the job done on time. It depends, in part, on the number of signatures submitted, whether there are legal challenges and whether there are other matters referred to the ballot at the same time, he said.

That could happen. Jon Garrido said Wednesday he intends to pursue his own referendum asking voters to repeal only parts of the law. If he, too, is successful, it would double the secretary of state's workload.

The Arizona Constitution says any measure that voters refer to the ballot cannot be enforced unless and until voters give their OK at the next available general election.

Chavez said his unidentified client wants to keep the law off the books as long as possible, if not permanently, through the referendum. He said the client, and the reason for objecting to the law, will be revealed soon.

Garrido said that because there may be provisions in the bill designed to promote public safety, he has instructed his lawyers to craft a referendum to "remove all the things that allow for racism to be displayed anywhere in Arizona, all the things that lead us to an apartheid state, all the things that cause people to be afraid of police."

He said the final language would be ready next week.

Garrido said he believes he can get the necessary signatures entirely with volunteer help.