Now Santorum targeted as rivals attack rising Republican star

Barely surfaced from a mostly unedifying televised debate in Arizona that veered from peevish to personal, Rick Santorum and Mitt Romney yesterday accused each other of failing the test of conservative consistency.

Smelling blood after a two-hour debate that seemingly left Mr Santorum the more seriously wounded, Mr Romney used an appearance before a builders' convention to twist the knife, mocking his rival for saying on stage that he had voted in Congress on occasion for initiatives he didn't like because he was following the party line. "He described it as 'taking it for the team' and I wondered what team he was taking it for," Mr Romney declared gleefully before a friendly audience at the luxury Arizona Biltmore hotel. "My team is the American people. I don't know if I have ever seen a politician explain in so many ways why he voted against his principles."

Mr Santorum may have fudged the opportunity on Wednesday night to show he has the stuff to ride his recent momentum in the polls, sparked by his clean sweep of three states two weeks ago, to finish off Mr Romney and snatch the Republican Party's presidential nomination. Instead he was frequently on the defensive against attacks not just from Mr Romney but also Ron Paul, the libertarian, who was in unusually ferocious form.

After nearly two unruly months, the Republican contest is at a pivotal moment. Both frontrunners are scrambling for advantage in this state and in Michigan, which both hold primary votes on Tuesday. Success or failure next week may frame their fortunes the following week on Super Tuesday when 10 states vote. There are three times more convention delegates at stake on just those two days than have been awarded so far.

Aides travelling with Mr Romney privately expressed confidence that they can take both states next week. Of the two, Arizona looks safest with an important number of Mormon Republican voters who will largely back the former Massachusetts governor.

But new polls yesterday showed a still slim lead for Mr Santorum in Michigan, the state where Mr Romney was born. Yesterday he unleashed a new television spot that scrolls through past quotes from Mr Romney which undercut his own conservative claims, including: "I don't line up with the National Rifle Association... I will preserve and protect a women's right to choose... I'd be embarrassed if I didn't ask for federal dollars every chance I had".

Mr Santorum's greatest difficulties on Wednesday night came when he was forced to explain why, before leaving Congress in 2006, he had voted against his principles in favour of steps that are mostly anathema to conservative voters, including supporting Planned Parenthood, the group that helps give women access to family planning.

"I find it really fascinating that, when people are running for office, they're really fiscally conservative," said Mr Paul. "When they're in office, they do something different." Early on in the debate he bluntly called Mr Santorum "a fake". Mr Santorum drew jeers from the audience as he tried to explain. "It was against the principles I believed in, but, you know, when you're part of the team, sometimes you take one for the team," he said.

Power pair giving big

The donations of only two men account for 71 per cent of contributions to a super-PAC backing Rick Santorum, according to Republican campaign funding figures revealed this week. Foster Friess, a supporter of Christian causes and retired businessman gave more than $1m. Mr Friess was recently forced to apologise for remarks he made about contraception in a TV interview: "Back in my day, they'd use Bayer aspirin for contraceptives. The gals put it between their knees."

William J Dore, head of Dore Energy Corp, also gave $1m.