EVERY foreigner in America, including British visitors, would be required to carry an ID card bearing photograph and fingerprints under plans drawn up by Rudolph Giuliani, the frontrunner for the Republican presidential nomination.

Giuliani is hoping to cement his status as the Republican favourite by promising to enforce immigration and border controls, drawing on expertise in combating crime from his time as mayor of New York. He announced last week that all foreigners, including holiday-makers, would be obliged to carry a “tamper-proof” biometric card, which could be issued at ports of entry.

“If you don’t have that card, you get thrown out of the country,” Giuliani said. He intends to call it a Safe card (for secure authorised foreign entry).

The proposal plays to his reputation for being tough on terrorism and shores up his credentials on immigration, but at the price of a row over civil liberties.

“The question is: in what circumstances will people be asked for their IDs?” said Jay Stanley, a privacy expert at the American Civil Liberties Union. “Will dark-skinned foreigners be asked for their IDs while a Caucasian person isn’t?” Opponents also believe it could be costly, cumbersome and could affect trade and tourism.

Giuliani said: “I did it back in 1994 with welfare people. It was a big, big, horrible thing that I was doing. I was asking welfare people to be biometrically identified by their fingerprints.

“It worked. It got rid of the duplicates and triplicates, people who were getting welfare at three different places.”

Giuliani has a liberal history of supporting immigration, which Mitt Romney, the former governor of Massachusetts and a leading rival for the Republican nomination, is trying to twist against him. Romney accused Giuliani last week of running New York as a “sanctuary” for illegal immigrants while mayor, provoking bitter ripostes about Romney’s own record as governor of the most left-wing state in America.

Under Giuliani’s plan, illegal immigrants would be allowed to obtain a card, work and ultimately become citizens - a route to legitimacy derided by some hardline Republicans as an “amnesty”. But Giuliani’s success as a former prosecutor and mayor who cracked down on criminals has given him unique credibility. He has vowed to strengthen patrols along the most porous parts of the border with Mexico and deport illegal immigrants who have been convicted of drug dealing and other crimes.

The intensity of the clash between Giuliani and Romney comes as the former mayor is proving his durability as the Republican favourite, despite many predictions of his demise at the hands of social conservatives.

Fred Siegel, author of The Prince of the City, a biography of Giuliani, said: “I feel I’m in the ‘I told you so’ position. People didn’t realise how good he is at what he does. He is a tough guy.”

Giuliani has a 10-point lead over Fred Thompson, the Hollywood actor and former Tennessee senator and his nearest rival for the nomination. Thompson is expected to enter the race officially after Labour Day, September 4, and spent last week gathering support in Iowa, an early voting state. But Thompson has lost some of the momentum and excitement that surrounded early predictions of his White House run, although he still has the potential to unite conservatives and take the lead.

Romney trails in fourth place in national polls, but remains strong in key states such as Iowa and New Hampshire and is hoping for early success there to propel him to victory in the Republican primaries.

Tom Edmonds, a Republican consultant who is supporting Giuliani, believes the party is beginning to take a good look at which candidate is the most electable. “We can be hard-nosed and lose or make the camp bigger and increase our chance of winning. The party realises it has to do more than ‘turn out the base’. It has to reach for the undecided voter and turn out the centre.”

A poll by Rasmussen last week showed Giuliani would beat Hillary Clinton in a head-to-head race by 47-40 points, a wider margin than any other Republican candidate. He has also won support by taking the fight to the Democrats – chiding them, for instance, for being too politically correct to mention Islamic terrorism in their televised debates.

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