PHOENIX — President Obama’s re-election campaign is dispatching workers across Arizona’s college campuses and Latino neighborhoods this spring, registering as many new voters as they can in an organized, three-month effort to determine whether they can put this unlikely state into play for Democrats this November.

By any measure the obstacles are considerable: Arizona has voted for precisely one Democratic president since Truman was in the White House. Yet Mr. Obama’s aides said in interviews that they thought it was possible they could move the needle of history by winning in 2012 a state that analysts believe is heading Democratic in national elections, but may not be there yet.

Obama strategists are simply following the same techniques they used in 2008 when putting states like North Carolina and Indiana into play. Then, too, there was much initial skepticism, though both states ended up going for Mr. Obama.

Yet for all those signs of organizing activity — and the fact that demographic and political changes across the West have made this region increasingly tempting ground for Democrats —Mr. Obama’s campaign strategists are not yet convinced he can win the state this November. Mr. Obama’s aides said they closely monitored the organizing here and would assess the result of their work over the next few months to see whether it made sense to pour money and resources into Arizona this fall.