Republicans handily won the state by a 9 percent margin in 2008, but the GOP nominee was Sen. John McCainJohn Sidney McCainThe Memo: Powell ended up on losing side of GOP fight A pandemic of hyper-hypocrisy is infecting American politics Virginia race looms as dark cloud over Biden's agenda  MORE (R-Ariz.), who was in the midst of his fourth Senate term at the time.

Poll director Bruce Merrill said Obama could be buoyed this fall by Democratic Senate candidate Richard Carmona.

"In Arizona, like the rest of the nation, political independents may determine who wins in November," said Merrill in a statement..

"The eventual outcome also may be dependent on whether former Surgeon General Richard Carmona can mount a vigorous campaign for retiring Sen. John Kyl's seat, a campaign that would stimulate turnout in the Hispanic community. While I think if the election were held today Romney probably would win, it appears Obama can mount a competitive campaign in Arizona."

Still, the state represents an uphill battle for Obama, with significantly more registered Republicans despite an influx of Democratic and Latino voters in recent years.

"It's important to remember the state's history: Arizona has supported only one Democratic presidential candidate since Harry S. Truman was elected in 1948. Winning Arizona will be an uphill battle for President Obama," said David Daugherty, director of research at Arizona State's Morrison Institute for Public Policy, in the statement.