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Two Republican presidential primaries will be held Tuesday. The Michigan primary is getting the most media attention because it could be the beginning of the end for former Massachusetts Gov. Mitt Romney.

But the national press corps is missing an even bigger story taking place in Arizona, which holds its primary the same day.

The GOP debate in Arizona included hints at the deep political rumbling taking place in the desert. In their competition to appeal to Arizona Republican primary voters, all the GOP rivals praised Arizona Gov. Jan Brewer as evidence of their deep red conservatism.

Support for the governor is a litmus test because of her decision to give police more power to stop people suspected of being illegal immigrants. That created a national controversy with outcry coming from anyone who looked like an immigrant, had an accent or feared racial profiling. It also prompted a court challenge from the Justice Department and several boycotts against travel to the state.

But the Arizona plan became a model for hard-right conservatives. They passed similar laws in Alabama, South Carolina and other states where Hispanics, both legal and illegal immigrants, now complain of civil rights violations. The fight even led to a now famous, finger-pointing confrontation between Gov. Brewer and President Obama.

The hidden consequence of the political divide over immigration in Arizona is that the once solidly red state -- it has voted for Republicans in nine of the last ten presidential elections -- now is considered by Democrats as up for grabs because the backlash to Gov. Brewer could give President Obama a re-election victory.

In the final weeks of 2011, Jim Messina, President Obama’s campaign manager, sent out a year-end fundraising appeal email to supporters. The email contained a video in which Messina updated them on the campaign’s strategy for winning 270 votes in the Electoral College.

Messina laid out six different scenarios whereby the campaign could win the necessary number of votes to re-elect President Obama. The first five of those scenarios focused on key battleground states like Florida, Ohio, North Carolina and Virginia.

But then Messina threw in a wild card, a scenario that would get Obama a second term that no one else had previously given much thought to: Win Arizona.

“Arizona wasn’t a swing state last time because Senator [John] McCain was there” he said, noting that Obama only lost to McCain in his home state by 8 points.  “There are hundreds of thousands of unregistered voters who are eligible there. We believe we can put Arizona into play and we’re beginning to work on the ground to do that.”

The demographics of the Grand Canyon State show that Messina may have something there.

The Hispanic population in Arizona is the fifth largest in the United States. Almost 2 million Hispanics live in Arizona, accounting for 4 percent of all the Hispanics in the nation. Thirty percent of the total population in Arizona is Hispanic, the fourth-largest Hispanic population share nationally.

There are nearly 800,000 eligible Hispanic voters in Arizona -- the fifth-largest Hispanic eligible-voter population in the country. For reference, California ranks first with 5.4 million. About 20 percent of eligible voters in Arizona are Latinos, making it the fourth-largest Hispanic eligible voter population share nationally.

The Hispanic vote will be critical in 2012 -- not just in Arizona but across the nation. The GOP’s hard-line position on immigration, for which Arizona was ground zero, has already begun to alienate this critical constituency.

One of the architects of the law, former President of the State Senate Russell Pearce, was recalled by his own constituents in a GOP primary last year largely because of his extreme positions on immigration. Elements of the new law have been blocked by federal courts and the Supreme Court has announced it will rule on whether it is constitutional.

The high court’s ruling is certain to make immigration a big issue in the general election.

Gov. Brewer is a national conservative political celebrity because of the immigration issue. She wrote a best-selling book, Scorpions for Breakfast, the highlight of which is a portrayal of herself as a heroine standing up to President Obama at a White House meeting on immigration.

Brewer won more praise from conservatives after she was photographed earlier this year pointing her finger in the President’s face and apparently yelling at him on an airport tarmac. She later fed far-right antagonism toward the president by incredibly telling reporters she felt “threatened” by the famously detached and cool president.

According to a recent Rocky Mountain poll, Brewer has a 37 percent approval rating. President Obama has a higher approval rating in the state at 40 percent.

Arizona will be getting a lot of attention this year, for its Senate and congressional races. Sen. Jon Kyl is retiring and U.S. Rep. Jeff Flake, a longtime opponent of wasteful spending and congressional earmarks, is running to replace him. Two popular Tea Party freshman, GOP Congressmen Ben Quayle and David Schweikert, are locked in a heated primary battle in the central part of the state because of redistricting.

And the resignation of Congresswoman Gabrielle Giffords from the House of Representatives has led to major speculation about her political future. Her miraculous recovery from an assassination attempt makes her an inspirational figure in her home state and nationally. She will be a potent campaigner for the president.

Watch the numbers coming out of Arizona next week carefully. The state may end up being the surprise of 2012.

Juan Williams is a writer, author and Fox News political analyst. His latest book is "Muzzled: The Assault On Honest Debate" (Crown/Random House).