He is a veteran candidate, with an isolationist and libertarian agenda perhaps more suited to a bygone era. But Ron Paul, one of the fringe Republicans, might just be capable of producing a surprise upset in the first of the Republican primary elections in Iowa, thanks to support from a unlikely quarter – the young.

His anti-war message, calling on America to stop acting as the world's policeman, is resonating, with more than 1,000 young people gathering in the Great Hall in Ames, Iowa, on Thursday night to cheer him repeatedly as he called on US troops to be brought back not just from Afghanistan but from Germany, Japan, Korea and 120 other countries round the world.

They cheered too as he opposed war in Syria or Iran, describing the nuclear threat posed by Tehran as overblown. More than 200 people, mainly students but also young people from round the state, including serving soldiers, stood in line afterwards to have their picture taken with him. It is one of the oddities of this campaign that the candidate attracting the youth vote is the oldest in the field, aged 76.

Paul, a long-time Congressman from Texas, said he does not know why he is proving popular with the young, beyond saying he may be old but he has "youthful ideas".

The US media tends to ignore Paul, regarding him, probably correctly, as a long shot for the White House, his isolationist and libertarian views too exotic for the Republican mainstream. In his 2008 election bid he suffered from attracting too many fringe and special interests groups, such as the Rolling Thunder vets who believe US troops are still secretly imprisoned in Russia, China and elsewhere.

But Paul has positioned himself better this time and his anti-war rhetoric is closer to the public mood. It is paying off. The Des Moines Register poll, normally the most reliable in the state, last week had Newt Gingrich on 25% and Paul on 18%, with Mitt Romney on 16%.

More significantly, Paul has adopted the Barack Obama playbook. Obama spent a lot of time in the state and built up a superbly efficient network of young volunteers who helped get his vote out in each of the 1,700 precincts. His victory in Iowa provided the momentum that took him all the way to the White House.

Meghann Walker, Paul's Iowa voter outreach director, is coy about disclosing how many precinct captains, responsible for getting out the vote on what will almost certainly be a chilly 3 January 3, she has recruited so far. But one volunteer said that two weeks ago the campaign had 150 out of 183 in Polk County, the most populous part of Iowa, and were pushing to find captains for the remainder: if those figures are replicated across the country, they are close to saturation point.

Iowa's Republican governor, Terry Branstad, said Paul's organisation was by far the best of all the Republican candidates.

Paul, like Obama, has devoted a lot of time to Iowa. He has visited once a week since May. Listen to the radio or put on the television in Iowa and there are regular ads in support of Paul. He has outspent his rivals in advertising in the state, paid for by the millions of dollars in donations coming in from small donations gathered on the internet.

Only Paul knows whether he believes he has a serious chance of becoming the next president or whether he is simply in the race because of the platform it provides to air his views. A win or second place in Iowa would provide him with a pretty big platform.

As well as being the most prominent advocate in the US today of isolationism, a strand in American thinking that can be traced back to revolutionary days and was at a high point in the Depression years, Paul favours drastic measures to reduce the country's $15tn deficit, pledging to cut $1tn in his first year as president. Much of those savings would come from ending US military involvement round the world – $4tn has been spent in the last decade in Iraq and Afghanistan – but also by cutting federal departments such as education and cutting back welfare programmes. He would also eliminate income and other taxes: smaller government would mean less taxes.

As a libertarian, he is opposed to measures such as the Patriot Act, introduced after 9/11. He regards the risk to American security as exaggerated and believes too much liberty has been sacrificed in the name of security. Among his supporters in the Great Hall was Gabe Lanz, 24, who is in the military and has done tours of duty in Iraq and Afghanistan. He is going to be one of Paul's precinct captains. He likes the idea of ending US involvement overseas. "He does not want to use us to fight other countries's wars for them. Let other countries be self-dependent. That resonates with me. Why do we always have to be the go-to-guys?"

The other big issue playing well with youthful voters is the deficit. They look at the $15tn and see it as a burden they are going to have to bear. Support in the Great Hall was not universal. A student at Iowa university, Emily Highnam, has not made up her mind yet who she will vote for. She liked Paul's anti-war message and plans to cut spending, but did not like the idea of cutting back on welfare.

A disproportionate slice of the Republican party in Iowa is made up of Christian evangelicals and home-schoolers, those who prefer to keep their children out of schools for a variety of reasons, including the teaching of evolution. Paul has been reaching out to them too. Among his extensive campaign literature is a Ron Paul Family Cookbook, full of recipes but mixed in with quotes from the Bible.

In Boone, a small town near Ames that looks as if it opted against moving on from the 1950s, Paul addressed a crowd of about 150 in the library. Among them was Joany Gorman, 49, mother of four and a home-schooler. Asked why she supported Paul, she pointed to the Cookbook. "The reason I support Ron Paul is because I believe Jesus Christ is the one true God," she said. She had never heard of him before this election but will vote for him on caucus day.