PHOENIX Republican Mitt Romney faces a new challenge in Arizona's February 28 presidential primary, where the growing momentum of rival Rick Santorum could threaten to derail what had been an expected romp for the on-again, off-again front-runner.
Romney was counting on Arizona to be his safety net as he fell behind Santorum in polls nationally and in his native state of Michigan, which holds a crucial primary the same day.
But Republican Party officials and activists in Arizona say Santorum's national surge has sparked new interest in his candidacy there, raising the possibility of another surprise in a topsy-turvy Republican nominating race that has seen repeated momentum shifts.
"I still see Mitt Romney as the guy to beat, but I'm not counting out Rick Santorum," said Russ Clark, a conservative talk radio host and chairman of the Colorado River Tea Party in Yuma, near the Mexican border.
"I think people accept Romney, but that's a lot different from liking Romney. They could shift just as quickly to Santorum," he said.
After being swept by Santorum in three states last week, a double dose of more losses in Michigan and Arizona would raise serious questions about Romney's viability as he heads into the 10 "Super Tuesday" contests scheduled for March 6.
Several polls showing Romney with a double-digit lead in Arizona were taken well before Santorum ignited his rise with victories in Missouri, Minnesota and Colorado - also states where Romney had been expected to do well.
A poll taken this week and released on Wednesday, by American Research Group, showed Santorum closing the deficit on Romney to 7 percentage points, 38 percent to 31 percent. The gap had been more than 20 points in January.
"The mood has definitely shifted away from Mitt Romney up here. There is an instant vetting of Rick Santorum going on," said Barry Weller, Republican chairman in Apache County, a small rural area in the mountains of north-central Arizona.
So far Santorum is largely leaving the state to Romney, who made a campaign stop in Arizona on Monday. Santorum has not organized in the state, has made no recent campaign stops here and aired no ads on state television.
Santorum has focused instead on Michigan and some Super Tuesday states where he hopes his brand of social conservatism will find a receptive audience.
'IT'S ALL ABOUT BUZZ'
He will spend a day in Arizona next week ahead of a high-stakes February 22 debate in Mesa with all four contenders - Santorum, Romney, former House of Representatives Speaker Newt Gingrich and Texas Congressman Ron Paul.
"Organization is one thing, but it's all about buzz, and there is a lot of buzz around Santorum," said Tom Morrissey, the Arizona state party chairman.
Despite the buzz, his lack of organization remains a stumbling block. Local party officials say they have seen no signs of the Santorum campaign and have no local contacts for interested voters.
"People are calling us saying 'Who can we contact?' And we're saying 'we're sorry, but as far as a contact - we don't have one,'" said Rob Haney, Republican chairman in Maricopa County, which encompasses Phoenix.
Romney has several political advantages in Arizona, including a large and active voting bloc of his fellow Mormons, a strong campaign organization and the backing of much of the state party establishment, including Senator John McCain.
His hardline stance on immigration and his businessman's pitch on curing the economy also work in his favor in Arizona, which shares a border with Mexico and has a high unemployment rate.
Republicans in Arizona have taken a tough stance on illegal immigration the centerpiece of a bitter state political battle, and Romney's hardline proposals include a promise to veto a bill that would help some children of illegal immigrants.
For many Republicans in Arizona, his business background and experience in running the Salt Lake City Winter Olympics are also positives. The state has an 8.7 percent unemployment rate, above the 8.3 percent national average.
"I'm really concerned about the economy and I think he's the guy who can turn it around," said Sandra LeSueur of Mesa, who attended a Romney rally on Monday night. "I trust him. He did wonders for the Salt Lake City Olympics."
Romney has been stressing his business experience as a contrast to the Washington-based careers of Santorum, a former U.S. senator, and his other rivals in race to choose a Republican nominee to face Democratic President Barack Obama in November.
With the exception of Paul, a doctor, "the other guys have spent their lives entirely in government," Romney told a big and enthusiastic Mesa crowd.
"We elected in President Obama someone who has never run anything, someone who has never been a leader," he said. "We're not going to do that in the Republican Party."
Clark Tomkinson, who manages a small real estate company in Casa Grande, said he believed the former Massachusetts governor could end the partisan bickering in Washington.
"I think Mitt Romney can build bridges where we have a divide in this country. I think he can bring us back together again," he said.
Romney also mentioned his faith during the Mesa rally. Mormons made up about one of every 10 voters in the Arizona Republican primary in 2008, when Romney finished second to home-state favorite McCain.
"My conservatism did not come so much from reading the writings of great conservative scholars as it did from living my life, my family, my faith, my business," Romney said.
Santorum has taken a lead in polls in Michigan, where Romney was raised and his father was a governor and car executive, but he would still be taking a risk of sorts by competing hard in Arizona.
The state's winner-take-all system means even a close second-place finish would earn him none of the state's 29 delegates to the August nominating convention.
"This has always been Romney's state to lose, and it doesn't seem to have changed," Haney said. "But if it's even close it won't look good for Romney."
(Editing by Doina Chiacu)