Former New York Mayor Rudy Giuliani favors building a fence to keep them out and wants them to speak English, Sen. John McCain wants at least 2 million of them deported and former Massachusetts Gov. Mitt Romney thinks McCain is soft on the issue.
To hear Republican presidential hopefuls solicit support before New Hampshire's January 8 nominating primary, you might think illegal immigrants were besieging the New England state, using its scarce services and taking local jobs.
Even though U.S. Census data reveals the Granite State as among America's whitest, the hot-button issue of how to secure the porous Southwest border with Mexico and what to do with 12 million illegal immigrants living in the shadows nationally comes up at Republican campaign appearances.
Voters say it is important to them.
During a campaign appearance on Sunday before about 200 voters in Plymouth, New Hampshire, Giuliani promised action.
"You need security at the border, a fence, a technological fence to stop people from coming in before they can be illegal," he said, noting the issue has been sidetracked by the war on terrorism.
Once the border is secure, Giuliani said of those immigrants permitted to remain, "Down the road if they want to become citizens ... they should have to read English, write English and speak English."
That line drew the loudest applause of his almost hourlong appearance. One woman said she was sick of seeing signs in English and Spanish at the hardware store, while another said the children born in the United States of illegal immigrants should not get citizenship.
Romney, trying to be the first Mormon U.S. president and running neck and neck with McCain in polls in the state, accuses McCain of favoring an amnesty for illegal immigrants.
"McCain pushed to let every illegal immigrant stay here permanently," one Romney TV ad in New Hampshire states.
McCain is from Arizona, where passions on immigration are intense.
In Iowa, which on Thursday kicks off the battle to pick candidates for the November election to replace President George W. Bush, Romney has made similar accusations at his main opponent there, Baptist minister and former Arkansas Gov. Mike Huckabee.
New Hampshire on January 8 will become the second state to pick a U.S. presidential candidate from each of the two main political parties. On Sunday, immigration came up repeatedly at a McCain event attended by several hundred at Newport's historic Opera House.
"The issue of illegal immigration may be one of the most emotional issues I ever encountered," said McCain, who initially supported a temporary guest-worker program for illegal immigrants but has shifted his position to emphasize border security first.
"There are about 2 million people here illegally who have committed crimes; those people should be deported immediately," McCain said, attributing those numbers to Homeland Security Secretary Michael Chertoff.
"We can't round up the other 10 million people and deport them all at once, so you are going to have to go step by step," he said, promising to first secure borders with "walls in urban areas, through vehicle barriers, with cameras and sensors."
New Hampshire is one of the American states least affected by immigration. U.S. Census data from 2005 shows Hispanics account for about 12.6 percent of the U.S. population. Of New Hampshire's 1.28 million residents, only 20,000, or about 1.5 percent, are Hispanic.
But with stepped-up immigration raids in New England in recent months and an increasingly rancorous national debate, analysts say it has become one of the big concerns for conservatives in the state.
"For conservative Republicans up here the hot button issue this year has not been abortion, it has not been guns or even Iraq, it has been illegal immigration," said Dante Scala, a political science professor at the University of New Hampshire. "(It) really makes conservatives see red up here."
"Immigration could be an issue that helps Romney to hold off McCain in those voter-rich, conservative, border towns," he added, referring to the wealthy, populous parts of southern New Hampshire that border Massachusetts where Hispanic immigration has been rising.
At McCain's rally, Alan Packman, 60, said the issue indirectly hurt his wallet. "We need a way to stop it and register them and get them paying taxes because they are attending our schools and hospitals and taking our social security."