Texas governor and presidential hopeful Rick Perry, speaks to supporters during a town hall meeting at Horry-Georgetown Technical College Sept. 5, 2011 in Conway, S.C.

Texas Gov. Rick Perry has been a battletested advocate for immigration enforcement for more than a decade in one of America’s most conservative states. Now, in what would have seemed implausible just a few years ago, the rising Republican star is in a fight  to convince his own party that he’s tough enough.

The emerging divide between Perry and GOP primary voters on immigration policy is a  high-stakes challenge for the presidential front-runner. But it could be most significant for the trend within the Republican Party it underscores: a rightward shift on an issue with implications for Hispanic support in 2012.

By many measures, Perry’s approach to immigration ought to please the party faithful.  In his decade-long term as governor, he cracked down on so-called sanctuary cities, imposed tough restrictions on drivers’ licenses for immigrants, and sent armed Texas Rangers to the border while demanding more federal boots on the ground.  He opposes a federal DREAM Act and a swift path to legalization for illegal immigrants.

“Of all the Republican candidates he’s the one who stands out the most on wanting to deal with this issue and put it to bed and resolve the problems,” said Jim Gilchrist, co-founder of the Minutemen Project, a Tea Party-aligned activist group that monitors activity along the U.S.-Mexico border.

His strong-arm approach in Texas has drawn criticism from Hispanic and immigrant groups who say he’s a far cry from the “moderate” some in his party now make him out to be.

“Perry has pushed the most anti-Hispanic agenda in a generation in Texas,” said San Antonio Mayor Julian Castro. “He would have a very difficult time appealing to the Hispanic community in 2012 because his policies and actions demonstrate such a lack of care and concern.”

Still, Perry has supported in-state tuition rates for illegal immigrant students and opposed construction of a full fence across the entire southern U.S. border. They’re positions he says reflect “heart,” but which his opponents say miss the mark.

“I don’t believe that for those people who came here illegally, we should be subsidizing with taxpayer money, through in-state tuition their education,” New Jersey Gov. Chris Christie said Tuesday night. “That is not a heartless position that is a commonsense position.”

“They are not residents of the United States,” Eric Fehrnstrom, communications director for Mitt Romney, said on MSNBC. “They have illegally entered this country and one of the reasons they come is because of magnets like in-state tuition where they can get a $100,000 benefit over four years of their education.”

The hard-line rhetoric and attempt to paint Perry as a paragon of liberalism is a sharp break with a Republican vision for immigration policy – tough enforcement with a dose of practicality – that was endorsed by each of the last three Republican presidents and majorities of voters in the party’s mainstream.

Texas is one of 13 states to support in-state tuition rates for immigrant residents, a policy backed nearly unanimously by the state’s Republicans. Former Florida Gov. Jeb Bush, a rising GOP star, says he thinks it’s a “fair policy.”

Moreover, a recent Pew Center poll found many Republican voters are more supportive of a pragmatic response to the nation’s 11 million illegal immigrants, favoring a conditional path to citizenship by 58 percent to 39 percent, even though all leading GOP presidential contenders stand opposed.

“It’s a telling sign of how much the Republican electorate’s expectation has evolved from Reagan – who would have been viewed as a leftist in this environment – but even former President Bush,” said former political strategist for George W. Bush and ABC News political consultant Matthew Dowd.

“You can’t have a thoughtful conversation about it in the Republican Party right now. You’re either [former U.S. Rep. and anti-immigration advocate] Tom Tancredo, or you’re for sanctuary cities,” he said.

Anxiety over the weak economy and high unemployment, security concerns post-9/11, and cultural unease surrounding sweeping demographic changes in American cities over the past two decades have encouraged a tougher line on immigration among Republican ideologues, who now stress border security alone.

Many in the current field of GOP presidential contenders oppose any effort to address the legal status of the country’s illegal immigrant population, some favoring the logistically impractical and potentially costly approach of deporting them all.

The leading candidates have courted immigration hard-liners Rep. Steve King of Iowa, Sen. Jim DeMint of South Carolina, and the man known as “America’s toughest sheriff,” Joe Arpaio, of Arizona – all seeking their endorsement for the coming campaign.

“The reason all the candidates are seeking his endorsement is because he’s a national figure among the conservative movement and a known commodity on ‘tough on crime’ and standing up for the rule of law,” said Chad Willems, political strategist for Arpaio.

Immigrant advocates, however, say association with figures like Arpaio and Gilchrist, who are viewed as extremists in immigrant circles, will hurt a Republican candidate’s appeal among Hispanic voters next fall.  They point out Arpaio has been investigated for civil rights violations and racial profiling, while Gilchrist’s group is labeled as a hate group by the Southern Poverty Law Center.

Moreover, several Republican candidates’ endorsement of Arizona’s controversial SB 1070 and similar measures in other states have further soured opinion in many immigrant communities towards a party they might otherwise consider supporting given disillusionment with President Obama.

“The party has become caught up in this spasm of anti-immigrant hysteria. It’s quite remarkable,” said Frank Sharry, executive director of Americas Voice, an immigrant advocacy group.

“You have Latinos and Latino immigrants now feeling unwelcome in this country, a state of siege in immigrant communities, a sense that the knock on the door or the slur or the firing or getting picked up while getting your kids at school,” he said. “That stuff haunts immigrants who are here legally and not every single day.”

Political analysts say the overarching tone and tenor of the debate may particularly jeopardize the appeal of a Republican presidential candidate among crucial Hispanic communities – the largest and fastest growing voting bloc –  in key swing states such as Florida, Nevada, Colorado and New Mexico.

Dowd, who helped Bush win reelection in 2004 with historic Hispanic support, said the consensus is that a GOP nominee would need to win 40 percent of the Hispanic vote in 2012 to capture the White House.

“I don’t think the rightward shift on immigration shuts the door” to widespread Hispanic support for a Republican candidate, said Dowd, “but it just makes the conversation slightly more difficult.”

“I think ultimately the general election for all voter groups will fall on the economy and jobs, and Obama will be judged on that. The rhetoric on immigration doesn’t make it easier, but I don’t think it’s a fundamental flaw for Republicans. But it is very telling for the primary process.”