The two proposed referendum drives challenging Arizona’s new sweeping law targeting illegal immigration are being abandoned, organizers said Monday. Andrew Chavez, a professional petition circulator involved in one of the efforts, said its backers pulled the plug after concluding they might not be able to time their petition filings in such a way as to put the law on hold pending a 2012 public vote.

Jon Garrido, the chief organizer of the other drive, attributed its end to a belief that the law would have been subject to legal protections under Arizona’s Constitution if approved by Arizona voters…

[T]he backers decided over the weekend to end the referendum campaign when they concluded there still might be a November vote, not giving them enough time to be confident about being able to wage a successful campaign against the law, Chavez said.