Rick Santorum won't win in New Hampshire.

The latest polls suggest the best he will do is finish third - but for a man voters struggled to identify just a few weeks ago, he has, through hard work and dogged campaigning, elbowed his way into the top tier of challengers for the Republican party nomination.

He spent a lot of time in Iowa. He went from meeting to meeting, diner to church hall, speaking with people, sometimes one on one, in each of Iowa's 99 counties.

When I visited the state in October, people were telling me he could be the big surprise, as the conservative-leaning voters in the state liked him and liked his message.

But as each of the revolving roster of front-runners in the Republican race has discovered, once you hit the front, people get a lot more interested in what you've said and what you've done in the past.

Italian roots

Santorum was the first of his family to be born in the US. A story he often tells on the campaign trail is how his grandfather travelled from Italy to work in the coal mines of Pennsylvania.

When he had saved enough money, which took five years, he sent for his wife and children, including Santorum’s father.

Much of his politics is informed by his upbringing and his Roman Catholic religion.

A father of seven living children - an eighth was born prematurely in 1996 and survived for just two hours - he is deeply opposed to contraception ("it's harmful to women").

He has argued against same-sex marriage arguing that could open the door to other unacceptable relations, equating homosexuality with bestiality or pedophilia.

So outraged by such a suggestion, one columnist asked readers to redefine "Santorum" as a disgusting sexual term, which now appears high in Google rankings if you enter the senator's name.

It takes a family

Santorum wrote a book - always a starting point for any presidential campaign - called It takes a Family seen at the time as a reply and rebuttal to Hilary Clinton's It Take a Village.

 Santorum argued "the influence of radical feminism" meant women found it more "socially affirming to work outside the home than to give up their careers to take care of their children".

Santorum got into the presidential battle in June last year - and immediately headed north to Iowa to begin his campaign.

While others used TV advertising to get their message across, the poor Santorum team couldn't match that  media buy.

And so he fought a ground war of attrition, holding more than 350 campaign events across the state in the past seven months.

The pattern reflected his entrance into national politics in 1990 at the age of 32.

With similar tactics, he unseated a seven term congressman in a staunch Democrat district in Pittsburgh.

He unseated a Democrat when he moved up to the senate in 1994.

However, he hasn't held office for more than five years, rejected by voters as he tried to win a third senate term.

Historic losing margin

Santorum's18-point losing margin was historic, and in such an important general election swing state as Pennsylvania, throws a huge question over his electability.

During his tour in Iowa, he didn't just address the issues he knew would play well with the slightly older, more conservative, more religious voters that make up large parts of Iowa’s Republican party.

He talked about the economy and carried a reasoned and nuanced argument about rebuilding America's manufacturing base.

In towns where jobs have been shipped, it played well.

And there is his constant message on the threat from Iran, arguing military action is necessary to prevent it building a nuclear weapon.

The tall former senator, known as "Rooster" in high school for his refusal to back down from an argument, is likely to finish third in New Hampshire, far, far behind Mitt Romney.

It's a more liberal state, his conservative views won't play well there.

Heckled by students

Santorum has already been heckled by students for his anti-gay stance.

But he knows the big battle for him is in South Carolina.

In two days after the Iowa result, his campaign received more than two million in donations.

It'll help him get his message across in the first southern contest and he's already spending some of that on TV time to introduce himself to voters.

But in South Carolina, he must establish himself first as the only strong conservative voice in the race, which would mean knocking out the Texas governor, Rick Perry.

And then he has to hope people see him as someone who can not only beat Romney but can credibly challenge Barack Obama in November.

The first is easier than the second - but a win in South Carolina and the rooster will be crowing.

Follow Alan Fisher through the US election campaign on Twitter: @alanfisher