The campaign needs 150,642 valid signatures of registered Arizona voters to qualify the initiative for the ballot this November.

"Voters want to have their say on whether Arizona should end marijuana prohibition," said Campaign Chairman J.P. Holyoak. "It's appearing more and more likely that they are going to have that opportunity. We're finding that most Arizonans agree marijuana should be regulated and taxed similarly to alcohol."

The proposed initiative would allow adults 21 and older to possess limited amounts of marijuana, establish a system in which marijuana is regulated similarly to alcohol, and enact a 15 percent tax on retail marijuana sales, from which a majority of the revenue would be directed to Arizona schools and public education programs.